RAGE (receptor for advanved glycation endproducts) was identified on endothelial cells as binding partner for AGE-modified molecules. The term "Advanced glycation endproducts" involves a number of structurally diverse molecules, which derive from multiple complex rearrangements of reducing sugars with free amino-groups of proteins. They evolve during food production and also in vivo during ageing and to an accelerated degree in diabetes, where AGEs cause receptor-mediated cellular perturbations. Due to the pathological relevance the aim of this thesis was to generate a "biosensor" for AGEs. To this end, the membrane-expressed receptor (flRAGE) as well as soluble RAGE (sRAGE) were expressed in mammalian cells and investigated in numerous binding studies. These did not reveal a specific interaction of AGE-modified ligands with RAGE. In addition, the expression of RAGE on endothelial cells, as described in the literature, could not be followed neither with the help of newly generated monoclonal anti-RAGE antibodies, nor in quantitative "real time" RT-PCR analysis. These results cast doubts on the meaning of RAGE as a proinflammatory receptor in AGE-mediated pathologies and on the adequacy of RAGE for the "biosensor". At the same time the question concerning a physiological role of the receptor arose. RAGE-expression was analysed in different healthy human tissues by "real time" RT-PCR, which revealed an almost selective expression in lung tissue. An important indication for a possible physiological function of RAGE in lung provided the selective localization of RAGE on alveolar epithelial type I cells as demonstrated in frozen lung sections as well as in in vitro cultivated lung cells. RAGE could be identified as a novel, highly specific marker for the thin, expanded AT I cell, which form part of the air-blood-barrier. In the following, RAGE was found to be an interaction partner for collagen IV, a major component of the alveolar basal lamina. Membrane-expressed RAGE did not only strengthened adherence of cells but also induced cell spreading on collagen IV-coated surfaces. This preferential interaction of RAGE with collagen IV could substantially contribute to the functional morphology of AT I cells in vivo, thereby ensuring an effective bidirectional gas-exchange. The results of this thesis expose a novel, so far unnoticed aspect of the biology of RAGE, which presumably contributes to the phenotypic characteristic und function of normal human lung tissue. / RAGE (receptor for advanced glycation endproducts) wurde als Interaktionspartner auf Endothelzellen für AGE-modifizierte Moleküle identifiziert. Unter den "Advanced glycation endproducts" werden eine Vielzahl strukturell unterschiedlicher Moleküle zusammengefasst, die durch mehrstufige komplexe Umlagerungen zwischen reduzierenden Zuckern und freien Aminogruppen von Proteinen entstehen. Sie entstehen sowohl bei der Herstellung von Lebensmitteln, als auch in vivo während des Alterns und in erhöhtem Maß bei Diabetes, wobei sie Rezeptor-vermittelt Zellstörungen hervorrufen. In der vorliegenden Arbeit wurde zunächst aufgrund der pathologischen Relevanz eine Strategie zur Konzeption eines "Biosensors" für AGEs verfolgt. Hierfür wurde sowohl der membranständige Rezeptor (flRAGE) als auch löslicher RAGE (sRAGE) in Säugerzellen exprimiert und in zahlreichen Bindungs- und Funktionsanalysen getestet. Hierbei konnte keine spezifische Interaktion der AGE-modifizierten Moleküle mit RAGE nachgewiesen werden. Auch die in der Literatur beschriebene Expression von RAGE auf Endothelzellen konnte mit Hilfe neu generierter monoklonaler Antikörper, sowie in quantitativen "real time" RT-PCR-Analysen nicht nachvollzogen werden. Diese Ergebnisse warfen Zweifel an der grundlegenden Bedeutung von RAGE als proinflammatorischer Rezeptor in AGE-bedingten Krankheiten auf und stellten damit auch dessen Eignung für einen AGE-Biosensor in Frage. Gleichzeitig warf diese Skepsis die Frage nach einer möglichen physiologischen Funktion dieses Rezeptors auf. Eine vergleichende Analyse der RAGE-Expression in verschiedenen gesunden Geweben mittels "real time" RT-PCR ergab eine nahezu selektive Expression in Lungengewebe. Wichtige Anhaltspunkte für die Funktion von RAGE in der Lunge ergaben sich aus der selektiven Lokalisation des Rezeptors auf Alveolarepithelzellen Typ I (AT I) sowohl in Gefrierschnitten der Lunge als auch nach in vitro-Kultur von Lungenzellen. RAGE konnte als neuer, hoch spezifischer Marker für die lang gestreckten AT 1 Zellen, die einen Teil der Blut-Luft-Schranke bilden, definiert werden. In folgenden Funktionsanalysen konnte RAGE als spezifischer Interaktionspartner für Kollagen IV, einer Hauptkomponente der Alveolar-Basalmembran, identifiziert werden. Membranständiger RAGE verstärkte nicht nur die Adhärenz von Zellen an Kollagen IV-beschichtete Oberflächen, er induzierte auch Zell-"Spreading". Dies gab Anlass für die Vermutung, dass die beobachtete präferentielle Interaktion von RAGE mit Kollagen IV maßgeblich zu der funktionellen Morphologie der AT I Zellen in vivo beitragen könnte, die die Voraussetzung für einen effektiven bidirektionalen Gasaustausch darstellt. Durch die Ergebnisse dieser Arbeit wurde ein neuer, bisher unbeachteter Aspekt der Biologie des RAGE aufgedeckt, der vermutlich entscheidend zur phänotypischen Ausprägung und Funktion des normalen humanen Lungengewebes beiträgt.

Main object of this study was to accelerate and to direct succession in the course of a 5-year field experiment on a mine spoil dump. The effects of (1) transplanting whole meadow turfs, (2) spreading meadow soil with turfs, (3) spreading diaspore-rich mown vegetation and (4) different types of management, as possible restoration techniques are discussed in the thesis

RAGE (receptor for advanved glycation endproducts) was identified on endothelial cells as binding partner for AGE-modified molecules. The term "Advanced glycation endproducts" involves a number of structurally diverse molecules, which derive from multiple complex rearrangements of reducing sugars with free amino-groups of proteins. They evolve during food production and also in vivo during ageing and to an accelerated degree in diabetes, where AGEs cause receptor-mediated cellular perturbations. Due to the pathological relevance the aim of this thesis was to generate a "biosensor" for AGEs. To this end, the membrane-expressed receptor (flRAGE) as well as soluble RAGE (sRAGE) were expressed in mammalian cells and investigated in numerous binding studies. These did not reveal a specific interaction of AGE-modified ligands with RAGE. In addition, the expression of RAGE on endothelial cells, as described in the literature, could not be followed neither with the help of newly generated monoclonal anti-RAGE antibodies, nor in quantitative "real time" RT-PCR analysis. These results cast doubts on the meaning of RAGE as a proinflammatory receptor in AGE-mediated pathologies and on the adequacy of RAGE for the "biosensor". At the same time the question concerning a physiological role of the receptor arose. RAGE-expression was analysed in different healthy human tissues by "real time" RT-PCR, which revealed an almost selective expression in lung tissue. An important indication for a possible physiological function of RAGE in lung provided the selective localization of RAGE on alveolar epithelial type I cells as demonstrated in frozen lung sections as well as in in vitro cultivated lung cells. RAGE could be identified as a novel, highly specific marker for the thin, expanded AT I cell, which form part of the air-blood-barrier. In the following, RAGE was found to be an interaction partner for collagen IV, a major component of the alveolar basal lamina. Membrane-expressed RAGE did not only strengthened adherence of cells but also induced cell spreading on collagen IV-coated surfaces. This preferential interaction of RAGE with collagen IV could substantially contribute to the functional morphology of AT I cells in vivo, thereby ensuring an effective bidirectional gas-exchange. The results of this thesis expose a novel, so far unnoticed aspect of the biology of RAGE, which presumably contributes to the phenotypic characteristic und function of normal human lung tissue. / RAGE (receptor for advanced glycation endproducts) wurde als Interaktionspartner auf Endothelzellen für AGE-modifizierte Moleküle identifiziert. Unter den "Advanced glycation endproducts" werden eine Vielzahl strukturell unterschiedlicher Moleküle zusammengefasst, die durch mehrstufige komplexe Umlagerungen zwischen reduzierenden Zuckern und freien Aminogruppen von Proteinen entstehen. Sie entstehen sowohl bei der Herstellung von Lebensmitteln, als auch in vivo während des Alterns und in erhöhtem Maß bei Diabetes, wobei sie Rezeptor-vermittelt Zellstörungen hervorrufen. In der vorliegenden Arbeit wurde zunächst aufgrund der pathologischen Relevanz eine Strategie zur Konzeption eines "Biosensors" für AGEs verfolgt. Hierfür wurde sowohl der membranständige Rezeptor (flRAGE) als auch löslicher RAGE (sRAGE) in Säugerzellen exprimiert und in zahlreichen Bindungs- und Funktionsanalysen getestet. Hierbei konnte keine spezifische Interaktion der AGE-modifizierten Moleküle mit RAGE nachgewiesen werden. Auch die in der Literatur beschriebene Expression von RAGE auf Endothelzellen konnte mit Hilfe neu generierter monoklonaler Antikörper, sowie in quantitativen "real time" RT-PCR-Analysen nicht nachvollzogen werden. Diese Ergebnisse warfen Zweifel an der grundlegenden Bedeutung von RAGE als proinflammatorischer Rezeptor in AGE-bedingten Krankheiten auf und stellten damit auch dessen Eignung für einen AGE-Biosensor in Frage. Gleichzeitig warf diese Skepsis die Frage nach einer möglichen physiologischen Funktion dieses Rezeptors auf. Eine vergleichende Analyse der RAGE-Expression in verschiedenen gesunden Geweben mittels "real time" RT-PCR ergab eine nahezu selektive Expression in Lungengewebe. Wichtige Anhaltspunkte für die Funktion von RAGE in der Lunge ergaben sich aus der selektiven Lokalisation des Rezeptors auf Alveolarepithelzellen Typ I (AT I) sowohl in Gefrierschnitten der Lunge als auch nach in vitro-Kultur von Lungenzellen. RAGE konnte als neuer, hoch spezifischer Marker für die lang gestreckten AT 1 Zellen, die einen Teil der Blut-Luft-Schranke bilden, definiert werden. In folgenden Funktionsanalysen konnte RAGE als spezifischer Interaktionspartner für Kollagen IV, einer Hauptkomponente der Alveolar-Basalmembran, identifiziert werden. Membranständiger RAGE verstärkte nicht nur die Adhärenz von Zellen an Kollagen IV-beschichtete Oberflächen, er induzierte auch Zell-"Spreading". Dies gab Anlass für die Vermutung, dass die beobachtete präferentielle Interaktion von RAGE mit Kollagen IV maßgeblich zu der funktionellen Morphologie der AT I Zellen in vivo beitragen könnte, die die Voraussetzung für einen effektiven bidirektionalen Gasaustausch darstellt. Durch die Ergebnisse dieser Arbeit wurde ein neuer, bisher unbeachteter Aspekt der Biologie des RAGE aufgedeckt, der vermutlich entscheidend zur phänotypischen Ausprägung und Funktion des normalen humanen Lungengewebes beiträgt.

3D environment reconstruction has received great interest in recent years in areas such as city planning, virtual tourism and flood hazard warning. With the rapid development of computer technologies, it has become possible and necessary to develop new methodologies and techniques for real time simulation for virtual environments applications. This thesis proposes a novel dynamic simulation scheme for flood hazard warning. The work consists of three main parts: digital terrain modelling; 3D environmental reconstruction and system development; flood simulation models. The digital terrain model is constructed using real world measurement data of GIS, in terms of digital elevation data and satellite image data. An NTSP algorithm is proposed for very large data assessing, terrain modelling and visualisation. A pyramidal data arrangement structure is used for dealing with the requirements of terrain details with different resolutions. The 3D environmental reconstruction system is made up of environmental image segmentation for object identification, a new shape match method and an intelligent reconstruction system. The active contours-based multi-resolution vector-valued framework and the multi-seed region growing method are both used for extracting necessary objects from images. The shape match method is used with a template in the spatial domain for a 3D detailed small scale urban environment reconstruction. The intelligent reconstruction system is designed to recreate the whole model based on specific features of objects for large scale environment reconstruction. This study then proposes a new flood simulation scheme which is an important application of the 3D environmental reconstruction system. Two new flooding models have been developed. The first one is flood spreading model which is useful for large scale flood simulation. It consists of flooding image spatial segmentation, a water level calculation process, a standard gradient descent method for energy minimization, a flood region search and a merge process. The finite volume hydrodynamic model is built from shallow water equations which is useful for urban area flood simulation. The proposed 3D urban environment reconstruction system was tested on our simulation platform. The experiment results indicate that this method is capable of dealing with complicated and high resolution region reconstruction which is useful for many applications. When testing the 3D flood simulation system, the simulation results are very close to the real flood situation, and this method has faster speed and greater accuracy of simulating the inundation area in comparison to the conventional flood simulation models

Phagocytosis is the process by which cells engulf foreign bodies. It is the hallmark behavior of white blood cells, being the process through which those cells ingest and degrade pathogens and debris. To date a large amount of research has focused on documenting the existence and role of biochemical components involved with phagocytosis. Scores of signaling molecules have been implicated in the complex signal cascade which drives the process. These molecules are small (typically no larger than 5 nanometers) and operate in a crowded, chemically “noisy,” environment, yet they coordinate the cell's activity over comparatively expansive distances (as large as 20 micrometers). How these molecular processes scale-up to coordinate the activities of the cell over such massive distances is largely unknown. Using a planar analog of phagocytosis termed “frustrated phagocytosis,” we experimentally demonstrate that phagocytosis occurs in three distinct phases: initial cell-antigen binding, symmetric spreading, and late-stage contraction. Initial binding and symmetric spreading appears to be both mechanically and chemically similar to the quasi-universal cellular behaviors of adhesion and migration. Adhesion and migration have received extensive attention from the biophysics community in recent years. Leveraging these similarities, we adapt the biomechanical frameworks used in models of migration to phagocytosis. We show that macroscopic properties such as a cell's effective viscosity and membrane cortical tension can be used to model cell behavior during phagocytosis. Our experiments reveal that late-stage contraction distinguishes frustrated phagocytosis from other spreading behaviors. This contraction is myosin dependent. Additionally we demonstrate, for the first time, that late-stage contraction corresponds with formation of a contractile F-actin belt. Based on the dynamic contraction model (DC) developed to explain actin structure during cell migration we propose a DC model of phagocytosis which posits that contractile belt formation is the result of a late-stage myosin activity coupled with F-actin.

People with a diagnosis of schizophrenia have been found to perform poorly on tasks assessing semantic memory, and these impairments have been proposed to be related to certain symptoms, in particular Formal Thought Disorder (FTD). A systematic literature review and meta-analysis identified the need a) to determine whether semantic memory is a primary impairment in schizophrenia and not secondary to other cognitive impairments and b) what cognitive models could provide the best explanation for the impairment. With these aims, Studies One and Two compared the performance of a group of people with schizophrenia across a battery of semantic memory tests (Hodges, Salmon and Butters, 1992). In order to eliminate confounding variables, two clinical control groups were recruited for comparison, one with a probable degraded semantic memory arising from Alzheimer‘s Dementia (AD) and the other with a primary dysexecutive syndrome caused by acquired brain injury (ABI). From these comparisons, it was possible to profile the semantic memory impairment in schizophrenia with the conclusion that any deficits are task-specific. Unlike the AD group, the impairment did not seem to arise from a loss of stored knowledge but nor did a retrieval problem, in its simplest terms, offer the best explanation. Since the ABI group performed normally on the battery it is clear that a dysexecutive syndrome does not necessarily explain poor semantic memory performance. Qualitatively, the associations and categories formed by people with schizophrenia on tasks of semantic categorisation e.g. the Category Generation Test (CGT) (Green, Done, Anthony, McKenna and Ochocki, 2004) often resemble loosening of associations and psychotic speech. In order to understand more about the processes involved in the formation of these bizarre categories, I compared performance on the CGT of groups of people with schizophrenia, AD and ABI. I found that the people with AD performed fairly similarly to the people with schizophrenia in that they sorted cards in an idiosyncratic way but the ABI group performed normally, adhering to taxonomic categories. Although this result might suggest that the bizarre associations on the CGT in people with schizophrenia are caused by a deficit in semantic memory (and not a dysexecutive syndrome), further analysis found important differences between the AD and the schizophrenia group in the way the card sorts were formed. In addition, both these groups showed intact semantic memory knowledge of the items they mis-sorted, indicating that categorisation problems do not necessarily arise from a degraded memory store. The difficulties people with schizophrenia appear to have on tests of associations and categorisation (e.g. CGT) could arise from a disorganised semantic memory i.e. differences in the way in which concepts are interconnected. On the CGT, patients with schizophrenia were far more likely to sort items on the basis of thematic (situational) information suggesting a preference for thematic over taxonomic associations. To test this, participants were tested using a triadic comparison task which requires choosing whether an item is best associated with a taxonomic, thematic or perceptually related item. On this test patients performed comparably to controls suggesting that their semantic memory is organised normally and that the abnormalities in the way in which items are associated on some semantic memory tests, including the CGT, are task-specific. It has been proposed that one of the core problems in schizophrenia is that there is ―an aberrant assignment of salience‖ (Kapur 2003) to contextually inappropriate concepts due to a dysregulated dopamine system (Kapur 2003; Kapur et al 2005). It is possible that this could also explain the semantic memory impairments in schizophrenia i.e. certain less relevant concepts/ associations are chosen because they are experienced as more salient. To test this, a group of patients with schizophrenia were assessed using a test of semantic salience. Compared to controls, the patients made significantly more errors of salience including significantly more errors where large aberrant attributions of importance were given to items. The tendency to make errors on the salience test was highly correlated with errors on the CGT and also the semantic association tests, indicating a common underlying mechanism. Therefore, it can be concluded that the semantic memory impairments in schizophrenia are task-specific, not caused by a loss of semantic knowledge or a dysexecutive syndrome, but due to an aberrant assignment of salience to less relevant semantic concepts. More work is needed to understand the cognitive processes underlying this aberrant attribution process, and also the biological substrates involved.

Climate change is one of the most important factor determining species ranges. In Europe there is now evidence for northward areal expansion in many Mediterranean insects including the praying mantis (Mantis religiosa). This species is the only representative of the order Mantodea inhabiting central Europe. The northern edge of the species distribution currently reaches latitude 53ř North. Although, the praying mantis is well known insect there is not enough evidence about its phylogeography. In this work three mitochondrial genes (COI, COII, Cyt b) were selected for phylogenetic study. Results indicate three statistically supported distinct lineages in Europe: Eastern European, Central European and Western European. Presumably these lineages are consistent with isolation during the last glacial and re-colonization from glacial refugia. Reduced haplotype diversity on the northern edge suggests currently established populations at the northern distribution border. To validate mtDNA results it was also considered four microsatellite loci. Due to different type of inheritance mtDNA and nuclear DNA it is possible to compare two independent genetic datasets. Microsatellite analysis confirmed results obtained on mitochondrial data. Three major genetic clusters were found: east, west and central. Spatial...

Les technologies modernes permettent d'avoir des renseignements toujours plus précis sur les interactions entre individus. Dans ce contexte, la collaboration SocioPatterns a permis de développer une infrastructure mesurant, avec une très grande résolution temporelle, la proximité face-à-face d'individus volontaires, portant des badges de radio-identification. Cette infrastructure a été déployée dans divers contextes, tels que des conférences scientifiques, un musée, une école ou encore un service hospitalier. La simple analyse de ces données représente un enjeu majeur pour l'étude de la dynamique humaine et soulève des questions aussi fondamentales que la recherche d'outils et de techniques d'analyse adaptés. Cette thèse présente la caractérisation statistique de la dynamique de proximité physique, mise en relation avec le contexte et les autres métadonnées disponibles, telles que l'âge, le sexe des individus, ou bien la structure de leurs réseaux sociaux virtuels. Si la structure des contacts diffère considérablement selon le contexte, les distributions empiriques des durées des interactions et entre interactions sont très similaires. Un modèle individu-centré, présenté dans cette thèse, propose des règles d'interactions microscopiques simples susceptibles de donner lieu à cette structure macroscopique complexe des temps d'interaction. Enfin, la caractérisation de la dynamique des contacts entre individus constitue une étape cruciale pour comprendre les mécanismes de propagation de maladies telles que la grippe dans une population. / Modern technologies allow to access to more and more detailed information on human interactions. In this context, the SocioPatterns collaboration has allowed to develop an infrastructure based on radio-identification devices, that records human proximity patterns at a fine grained resolution, among voluntary individuals. This infrastructure has been deployed in diverse contexts, such as scientific conferences, a museum, a primary school, or a hospital department. The mere analysis of these data represents a high stake for the study of human dynamics and raises fundamental issues such as the need of adequate tools and analysis techniques. This thesis presents the statistical characterization of physical proximity dynamics, put into relation with the context and other available metadata such as the age, the gender of participants or the structure of their virtual social networks. Although contact patterns considerably differ amongst the various contexts, the empirical distributions of interaction durations and of inter-contact times are very similar. An agent-based model, presented in this thesis, suggests simple microscopic interaction rules able to produce the complex macrostructure of interaction durations. In the last place, the characterization of contact dynamics constitutes a determining step for understanding spreading mechanisms of diseases such as the influenza. The human proximity data have allowed to analyze the level of information needed on contact dynamics for the elaboration of epidemiological models of contagion. Such models allow to better estimate the impact of public health strategies, e.g. the closure of school classes and targeted vaccinations.

Les lymphocytes T (LT) doivent analyser efficacement un nombre important de cellules présentatrices d'antigène (CPA) afin de détecter un antigène spécifique et d'initier une réponse immunitaire adaptée. La reconnaissance par le récepteur des cellules T (TCR) d'un peptide spécifique associé au complexe majeur d'histocompatibilité (pMHC) doit donc être extrêmement sensible et rapide. Alors que les voies de signalisation en aval du TCR sont largement étudiées, la cinétique de la discrimination des ligands par le TCR et de l'activation initiale du LT reste mal connue. Des surfaces solides recouvertes de ligands du TCR nous ont permis d'étudier les événements cellulaires initiés par la détection d'un antigène. L'utilisation de la microscopie a fluorescence par réflexion totale interne (TIRFM) et la microscopie interférentielle (IRM) nous a permis de montrer que l'interaction initiale entre surface et LT est attribuable à des microvillosités mobiles. La stimulation du TCR active en quelques secondes un mouvement de rétraction de ces microvillosités. Ces mouvements actifs sont régulés par l'activation de la PLC- γ1 et sont dépendants des myosines (IIA, Ic et Ig), de la cofiline et de l'ezrine. Après cette phase d'analyse de l'environnement extracellulaire, la stimulation du TCR entraîne l'étalement rapide et actif de la cellule. L'amplitude et la vitesse d'étalement reflètent l'efficacité activatrice du ligand reconnu par le TCR. En moins de 5 minutes différents pMHC, ayant des propriétés biophysiques proches, sont donc discriminés par les LT et capables d'induire une première réponse cellulaire spécifique. / T lymphocytes need to efficiently probe a large number of antigen-presenting cell (APC) in order to detect an agonist antigen and to initiate an effective immune response. Therefore, engagement of the T-cell receptor (TCR) by peptide-bound major histocompatibility complex (pMHC) is a highly sensitive and rapid process. While signaling pathways downstream the TCR are extensively studied, little is known about antigen discrimination kinetic and initial T-cell response.Model planar surfaces coated with TCR ligand allowed us to study cellular events initiated by antigen detection. Using TIRFM (total internal reflexion microscopy) and IRM (interference reflexion microscopy) we showed that T-cell initial contacts with the surface were mediated by mobile microvilli. TCR engagement triggers a pulling motion of T cell surface microvilli within seconds. Active microvilli movements are dependent on PLC-γ1 activation and on the presence of myosins (IIA, Ic and Ig) as well as cofilin and ezrin. After this extracellular environment probing period, TCR stimulation triggered a rapid and active cell spreading. Cell spreading amplitude and speed reflect the ligand activating efficacity. In less than 5 minutes pMHC with different biophysical properties were discriminated by T-cells and triggered a first specific cellular response.

<p>Sorghum [<i>Sorghum bicolor</i> (L.) Moench] is a staple food for millions of people in Africa and South Asia. It is mainly consumed for its starch. The starch composition and structure in the seed endosperm determines cooking properties, processing quality, and starch digestibility. </p> <p>An assay to measure the alkali spreading value (ASV) of sorghum is described. The assay was used to identify sorghum EMS mutants with variation in starch composition. The ASV mutants (ASV+) exhibited a range of starch thermal properties with starch gelatinization temperatures (GT) being lower or higher than samples from Tx623 or Sepon82. The ASV+ phenotypes were found to be correlated with starch related traits such as enthalpy (r = −0.53) and range of starch GT (T_c-T_o) (r = 0.60). </p> <p>Genes controling the ASV phenotype of sorghum and their impact on starch quality traits are described. Whole genome re-sequencing of sorghum EMS mutants exhibiting an ASV+ phenotype was used to identify single nucleotide polymorphisms (SNPs) in candidate genes <i>Sobic.004G163700</i> and <i>Sobic.010G093400</i>. The two genes were identified as a <i>SbeIIb</i>, a putative sorghum homolog of <i>amylose extender,</i> and as a <i>SSIIa</i>, respectively. Linkage analysis showed that the mutations in <i>Sobic.010G093400</i> and <i>Sobic.004G163700</i> co-segregated with the ASV phenotype. The <i>ssIIa</i>-mutants exhibited normal amylose values, lower starch GT and lower final viscosity than the wild type. The <i>sbeIIb</i>-mutants exhibited higher amylose content, higher starch GT and lower peak and final viscosity with poor gel consistency compared to the wild type and <i>ssIIa</i>-mutants. An allele dosage test indicated that the <i>sbeIIb</i>-mutants had an allele dosage dependent effect on amylose content. Double mutants of <i>sbeIIb</i> and <i>ssIIa</i> showed that amylose content, starch thermal properties and paste viscosity profiles resemble the <i>sbeIIb</i> parent. </p> <p>A study of ASV phenotypes in a panel of more than 750 sorghum conversion lines revealed genetic variation for the ASV phenotype. A few SC-lines exhibiting stable expression of the ASV+ phenotype over two growing seasons. Most of these lines were described as belonging to the working group Nandyal, durra types from India described as producing ‘glutinous grains’. Whole genome resequencing discovered common SNPs in genes associated with starch biosynthesis. A genome wide association study (GWAS) identified a significant SNP that could be associated with the starch biosynthesis gene <i>Sobic.010G273800</i>, and with candidate genes <i>Sobic.010G274800</i> and <i>Sobic.010G275001</i> both annotated as glucosyltransferases. Grain samples from SC489, SC491, SC587 and SC589 exhibited a consistent ASV+ phenotype with lower or similar starch GT, similar amylose content, and similar high viscosity and gel consistency compared to controls.</p> <p> </p>