碩士 / 國立彰化師範大學 / 生物學系 / 93 / Crustacean hyperglycemic hormone (CHH) is a neurohormone originally identified in the X-organ sinus gland (XO-SG) of the eyestalk ganglia and primarily involved in the regulation of carbohydrate metabolism. Sequence analysis of CHHs isolated from various decapod crustaceans shows that they are peptides of 72–73 amino acid residues. The present study presents data indicating that CHH-like molecules are expressed in the hemocytes of the crayfish Procambarus clarkii. Significant levels of CHH-immunoreactivity were detected in the hemocyte extracts by a sandwich ELISA using antibodies raised against SG-CHH. Furthermore, three cDNA sequences, dubbed TG/CG-CHH, Hem-CHH1, and Hem-CHH2, respectively, were identified using PCR (polymerase chain reaction)-based cloning methods. Conceptual translation of these sequences revealed that TG/CG CHH encodes a typical CHH (72 residues) that shares a common sequence with the CHH first found in the crayfish cerebral and thoracic ganglia, whereas Hem-CHH1 and Hem-CHH2 each encodes a CHH-like peptide (40 residues) that is identical in sequence to the first 40 residues of the crayfish SG-CHH and TG/CG-CHH, respectively. Western blot analysis of hemocyte extracts also revealed the presence of CHH-immunoreactive bands. Immunofluorescence analysis demonstrated the presence of CHH-immunoreactivity, and existence of both L-phe3-CHH and D-phe3-CHH immunoreactivity in the granular cells. Three major CHH-immunoreactive fractions were separated by RP-HPLC. The combined results not only show for the first time in any crustaceans that hemocytes express CHH-related molecules, but also add unique CHH variants to the existing repertoire of CHH molecular polymorphism. It is postulated that these CHHs may play important roles in immune functions performed by the hemocytes, and possibly served as signal molecules involved in the crosstalk between neuroendocrine and immune system.
| Identifer | oai:union.ndltd.org:TW/093NCUE5112015 |
| Date | January 2005 |
| Creators | Su-Hua Wu, 吳素華 |
| Contributors | Chi-Ying Lee, 李奇英 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 98 |
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