Study On The Expression And Localization Of MATP In Different Colors Of Alpaca Skin

MATP (membrane-associated transporter protein) is eye skin albino IV (OCA4) gene and it’s coding the membrane-associated transporter protein which plays an important role in the melanosome, may participate in the melanin synthesis and transport of melanosome substances necessary for normal operation. Therefore, MATP gene was took as candidate gene affecting the formation of alpaca’s hair color, and was studied by using several biological methods, which in order to search the relationship between expression quantity of MATP gene and hair color, establish the theoretical basis for the research of alpaca’s coat color and genetic mechanism.(1) Alpaca’s MATP gene partial cDNA (218bp) were determined by using RT-PCR, and the cDNA fragments were compared with other animals sequence in the NCBI. The result shows that MATP gene sequences with other species have high homology, identified as alpacas MATP gene sequences.(2) qRT-PCR was using to analysis MATP genes relative expression in alpaca skin tissue of different hair color. The results showed that:the mRNA quantity of MATP in the brown alpaca’s skin tissue was3.047times (P<0.05) than ones of white alpaca after correction of housekeeping gene.(3) Western blot was using to analysis expression of MATP protein in alpaca skin tissue of different colors, the result showed, there always exist the molecular weight of53KD protein which can combine with goat polyclonal antibody against MATP protein in the extract of skin tissue. The gray value of protein bands were measured by using software and the conclusion was normalized by p-actin gene acting as an internal calibration for the purpose of semi-quantitative analysis. The average relative gray value of MATP protein in skin tissue of white alpaca was1.5968±0.7908, and the average relative gray value of MATP protein in skin tissue of brown alpaca was3.4456±0.3564. Differences were significant (P<0.05).(4) Immunohistochemical method was using to observe alpaca skin structure and found it was similar with other animals. MATP is widely distributed in the epidermis, dermis papilla and root sheath. Results showed that average optical density of positive cells locating in the brown alpaca’s skin follicle was higher than ones in white alpaca. Differences were extremely significant.In summary, the results showed that the mRNA and protein expression level of MATP in skin tissue of brown alpaca were higher than white ones. The difference showed that the expression level of MATP was associated with the coat color. MATP was involved in the process of coat color formation.