Functional analysis of MSTN promoter in scallop (Chalmys nobilis)

In order to investigate the negative regulater role of myostatin (MSTN) in growth and development of adductor of Chalmys nobilis, we analyzed the promoter sequence of MSTN of C. nobilis. The results show that the promoter sequence was 1 358 bp in length, including four transcription start sites (TSS). The core promoter region was located from –100 bp to –51 bp. Two kinds of cis-regulatory element, a TATA-box (located from –92 bp to –86 bp) and two E-boxes, were detected in promoter. Potential transcription factor binding sites including MEF2, MEF3, FoxO, MTBF, MyoD and so on were found in promoter. No CpG island was found. Six luciferase expression vectors with different lengths of MSTN promoter were successfully constructed and transiently transfected into 293T cells for an analysis of the activity of dual luciferase reporter gene. It is shown that all the six promoter sequences had transcriptional activity, with PGL-534 the highest, followed by PGL-274, PGL-22 and PGL-102, and PGL-995 the lowest. There might be some binding sites of potential negative transcription factors from –216 bp to –364 bp, and potential positive transcription factors from –364 bp to –825 bp.