Distribution Of Melanocyte And Gene Differential Expressed Research

This study through different histochemical staining and real-time quantitative polymerase chain reaction (RT-QPCR) to explain melanocytes distribution,shape and melanin deposition related genes expression in different organs of Black-boned goat, in order to explain the reason for the melanin trait of black-boned goat.We used immunohistochemistry staining,dopa staining and hematoxylin eosin(HE)staining study the location and characteristics of melanocyte of black-boned goat, used real-time quantitative PCR to study Microphthalmia associtate transcription factor(MITF),melanocortin receptor1(MCI R), endothelin3(ET-3), the family of tyrosinase(TYR,TYRPl,tyrp2) relative expression in different Black-boned goat organs. It can explain and provide the reference for the reason of melanin deposition and molecular genetic mechanism of about Black-boned goat. The results are as follows:The immunohistochemistry results showed that melanocytes were mainly located in basal layer of epidermis and hair follicles, not seen in other organs;The DOPA staining revealed that melanocytes distribute in the bulb of black hair follicles and outer root sheath, this melanocytes can secrete a large number of melanin, not seen in other organs.The hematoxylin-eosin(HE)staining results showed that melanocytes in the outer root sheath of black hair follicles have intense pigmentation and tenedency for vacuolization while melancoytes in white hair follicles were elliptical shape and produced no melanin.Gene differential expression study results:Using SYBR Green I dye prodecure,6melanin synthesis related genes were selected to detected the transcriptional level in different organs of black-boned goat by fluorescent quantitative PCR,and each group was repeat three times, the results showed as average±standard error,using LSD multiple comparisons in PASS16.0software analyze data.The results shows:MITF and MC1R wree widely expressed in Black-boned goat,they express in nine organs and played a major role of the secretion of melanin.MITF was highest expressed in white skin, heart, liver, tongue and hamstring,MC1R was highest expressed in spleen and lungs,MITF and MC1R were have higher levels of expression in other organs.Bacuse cAMP can raise MITF and MC1R expression level and plays a significate role in the cyclic adenosine pathways,so the cAMP pathways may have important influence on the Black-boned goat melanin deposition; TYRPl mRNA expression in black skin is22.7times as high as white skin;In black skin, the TYRP1mRNA expression is1.57,52.6,1.4,11.9and14.8times than MITF,EDN3,MC1R,TYR,TYRP2. So we speculate TYRP1may play a major roal for the melanin trait of black-boned goat, but molecular genetic mechanism and influence factors of TYRP1need further research.