The Function Of α-MSH And Lpa-miR-nov-66 On Melanogenesis Of Alpaca (Vicugna Pacos)

lpa-miR-nov-66 is a novel microRNA expressed in the alpaca skin, which plays an important regulatory role in the process of the melanogenesis. α-MSH is an important neuroendocrine hormone,which affects the formation and distribution of melanin in the skin through the regulation of MC1R. Here, the function of lpa-miR-nov-66 andα-MSH on melanogenesis by transfection of lpa-miR-nov-66 and the exogenous addition of a-MSH in melanocytes, in vitro. The main results were as follows:1 The real-time monitoring cell detector found that, compared with the control group, there apperaed the different proliferation without significant difference till 35h of the cell growth.2 mlpa-miR-nov-66A and protein expression were detected by qRT-PCR and Western blotting, lpa-miR-nov-66 expression of addition group is 0.24±0.012 fold of control group,and showed significant differences (P<0.01),respectively and the results showed that compared to the control group, the expression of transfected group, addition group, transfected and addition group the amount of MITF are respectively 0.16±0.014 folds/0.90±0.07 folds,2.03±0.051 folds/1.24±0.09 folds,0.30±0.013 folds/1.12±0.06 folds and showed significant differences (P<0.01); the expression of TYR decreased by 0.73 ±0.033 folds/0.85±0.05 folds、up 4.67±0.14 folds /1.69±0.14folds、2.54±0.21folds/1.27±0.11folds and showed significant differences (P<0.01).3 The intracellular cGMP and cAMP content were measured by ELISA method. The results showed that compared to the control group, cGMP content in transfected group、addition group、transfected and addition group is 0.149±0.012 folds、2.68±0.17folds and 2.267±0.12 folds, with significant differences (P<0.01); compared with the control group, cAMP content in transfected group, addition group, transfected and addition group was 0.57±0.042 folds,2.07±0.19folds and 1.36±0.124 folds, with significant difference (P<0.01).4 Melanin production was measured by ELISA in all experimental groups. The results that that compared to the control group, the melanin production in transfected group, addition group、transfected and addition group was 0.58±0.043 folds,3.27±0.27 folds and 1.81±0.16folds, with significant difference (P<0.01).Conclusions: the lpa-miR-nov-66 and a-MSH have functions cooperatively on the melanogensis of alpaca through the regulation of the cAMP pathway.