Studying On Genes Related With Melanin In Black Chicken

The "black" is a cardinal character of black chicken and is very important for the medical value and economical value of black chicken. At present, the studying on the "black" character of black chicken is mainly involved in generation, distribution and structure of melanin in black chicken. The identification of genes related with the "black" character of black chicken will establish root for the following:(l)making clear the mechanism of "black" character formation of black chicken. (2)ascertaining the medical function of black chicken. (3)improving gene by gene engineering and breeding methods, and obtaining breed variety of chicken and related engineering medicine. (4) even implying these related genes to other organism. The study compare firstly gene expression between black chicken and non-black chicken by the methods of PACS and 8 differential display , and obtain some differentially expressed coding sequence tags (dCST) and expressed sequence tags(EST). According to the results of sequence analysis, combining to known gene function and gene expression analysis, some possible related genes are identificated.The main achievement of the study is as follows:l.The results of gene differentially expressed analysis by two methods show that there are some distinct mRNA types between liver tissue of black chicken and non-black chicken, which is in accord with the theory that the "black" character of black chicken is controlled by many gene.2. 8 differentially expressed coding sequence tags(dCSTs) between black chicken and non-black chicken are obtained by preferential amplification of coding sequence of mRNA of 15%. Of 8 dCSTs, 2 dCSTs (A33, C13) have high homology with PLSK8970 vector sequence, and 1 dCST(B59) has high homology with 23S rRNA gene, and ldCST(A13) has high homology with chicken connect/titin gene, and 4 dCSTs(A37, A41, B19, C60) are novel gene fragments.3. 29 differentially expressed sequence tags(ESTs) between black chicken and non-black chicken are obtained by deta differential display methods. Of 29 ESTs, 13 ESTs have high homology with known genes, and 9 ESTs has homology with ESTs in database. 4 ESTs are novel gene. Of 13 known ESTs, 8 ESTs (A17, B57, A36, B36, A35, D36, C39,D9) respectively have homology with chickenbeta-trepomyosin gene, cardiac myosin alkali light chain gene, insertionally activated oncogene, fra-2oncogene, 16SrRNA gene and mitochondrion genome sequence; 5 ESTs (B53, B109, B20, C26, D31) respectively have homology with humnan TIN gene, human phosphoglucomutase5 gene, human mouse signal recongnition particle 54kDa gene, human mouse ribonuclease/angiogenin inhibitor gene of which homologous gene in chicken are still not cloned.3. According to gene function analysis of differential fragments and combining to those study results related with melanogenesis, regulation, transport and migration of melanin, 1 dCST(A13) and 3 ESTs(A17, B53, B57) are related with "black" character of black chicken.The 4. differential fragment show significant homology to myosin of chicken or human. The myosin is necessary for the localization of melanosomes , either by active transport or tethering.5. The result of gene expression analysis of A36 which have high homology with chicken insertionally activated c-Ha-ras oncogene shows that A36 is expressed in all non-black chicken and is not expressed in all black chicken. Therefore, the expression of A36 is related with the "black" character of black chicken. No report which involve the relation between oncogene and the"black" character of black chicken is found country inside and outside.The study think there possibly exists two aspect to relation between oncogene and the "black" character: (1) The normal expression of oncogene suppress melanogenesis or transport of melanin. (2)The abnormal expression of oncogene stimulate the formation of the "black" character of black chicken.6. The results of gene expression analysis confirm that the expression of 2 known EST(B20, D36) is related with the "black" character in black chicken. The 2...