紫光对斑马鱼皮肤黑色素细胞数量及相关基因表达的影响

Effects of UV illumination on number of melanocytes and expression of related genes in sws1 mutant zebrafish

利用CRISPR/Cas9基因编辑技术构建感紫光短波视蛋白(short-wave-sensitive 1,sws1)基因缺失的斑马鱼突变品系sws1^(-/-)。检测紫光照射后野生型AB品系和sws1^(-/-)突变品系在背腹皮肤中黑色素细胞的数量、黑色素合成相关基因pomc和asip、视黄酸合成相关基因raldh2和raldh3的表达量。结果显示:在紫光照射60和100 d后,sws1^(-/-)斑马鱼背部皮肤黑色素细胞数量显著少于野生型斑马鱼(P<0.05);实时荧光定量PCR (qRT-PCR)检测发现,pomc基因在紫光照射100 d的sws1^(-/-)斑马鱼背部皮肤中的表达量显著低于野生型,raldh2在紫光照射100 d的sws1^(-/-)斑马鱼背部皮肤中的表达量显著低于野生型。研究表明,紫光可能通过SWS1影响背部皮肤raldh2的表达从而影响视黄酸的合成,再通过影响pomc的表达调控黑色素细胞的形成。研究结果为分析紫光基因调控鱼类皮肤黑色素细胞形成的分子机制提供了基础。

The short-wave-sensitive 1(sws1) gene was knocked out using CRISPR/Cas9 technology in zebrafish. Under UV illumination, the numbers of melanocytes were calculated and the expression levels of melanocyte formation related genes pomc and asip, retinoic acid synthesis related genes raldh2 and raldh3 were determined in the dorsal and ventral skins of AB wild type and sws1^(-/-)zebrafish. It showed that: the number of melanocytes in the dorsal skin of sws1^(-/-)mutant was significantly less than that of wild type after exposing to UV light for 60 and 100 days;qRT-PCR showed that the expression of pomc in the dorsal skin of sws1^(-/-)mutant zebrafish was significantly lower than that of wild-type after 100-day UV illumination;the expression of raldh2 in the dorsal skin of sws1^(-/-)mutant zebrafish was significantly lower than wild-type after 100-day UV illumination. This research suggested that UV light could influence the expression of raldh2 and the synthesis of retinoic acid through sws1, and then affected the expression of pomc to regulate melanocyte formation. This result provided a basis for understanding the molecular mechanism of sws1 regulation on melanocyte formation of the fish skin.