MyoD control of SKIP expression during pig skeletal muscle development

Abstract

Skeletal muscle and kidney enriched inositol phosphatase (SKIP) was identified as a 5'-inositol phosphatase that hydrolyzes PI(3,4,5)P3 to PI(3,4)P2 that negatively regulates insulin-induced phosphatidylinositol 3-kinase signaling in skeletal muscle. In this study, we obtained a 1575-bp mRNA sequence of porcine SKIP that included the full coding region encoding a protein of 450 amino acids. With the use of comparative mapping, we mapped this gene to SSC12 q1.3, where many QTLs affect Backfat thickness at 10th rib, carcass yield, the number of muscle fibers, and ham weight traits. As a candidate gene for growth and carcass traits, a novel single nucleotide polymorphism in exon 12 (G>A) was detected by PCR-RFLP. The results showed that the GG genotype had higher skin percentage (SP), carcass length to first spondyle (CL1), carcass length to first rib (CL2), but lower intramuscular fat (IMF) as compared with genotype AG (P<0.05), and allele G seemed to be associated with an increase in the growth trait. Porcine SKIP was expressed abundantly in skeletal muscle tissue and was transcriptionally upregulated during skeletal muscle differentiation. Analysis of the porcine SKIP promoter sequence demonstrated that MyoD was involved in regulating SKIP mRNA expression in myotubes, partly via the cis-acting elements in SKIP promoter. In summary, we suggested that SKIP might play a role in the regulation of skeletal muscle development in pigs.

Role of Phosphatidylinositol 3,4,5-Trisphosphate (PIP3) 5-Phosphatase Skeletal Muscle- and Kidney-enriched Inositol Polyphosphate Phosphatase (SKIP) in Myoblast Differentiation

“…1, A and B). During the development of pig skeletal muscles, MyoD has been shown to control SKIP expression (10). In C2C12 cells, expression of MyoD resulted in higher expression of SKIP after the initiation of differentiation for 48 h (Fig.…”

“…Cells were imaged using a confocal microscope (Olympus Co., Tokyo, Japan). 3 5-phosphatase abundantly expressed in skeletal muscles; the transcription of SKIP increased within 72 h of induction of differentiation in C2C12 cells (10). To examine the role of SKIP in myoblast cell differentiation, we monitored SKIP expression in C2C12 cells during differentiation.…”

“…It has recently been reported that muscle-specific transcription factor MyoD controls SKIP 2 expression during muscle cell development (10). MyoD is required for expression of SKIP in skeletal muscles, partly via cis-acting elements in the Skip promoter, and the expression level of SKIP was up-regulated in early differentiated C2C12 myoblast cells.…”

Characterization of porcine SKIP gene in skeletal muscle development: Polymorphisms, association analysis, expression and regulation of cell growth in C2C12 cells

“…IFR, internal fat rate; CL2, carcass length to first rib; LD MM, m. longissimus dorsi meat marbling; BF MM, m. biceps femoris meat marbling; and LD IMF, intramuscular fat. the exon 2 insertion in any tissues and submitted only one clone of porcine SKIP gene to GenBank (Xiong et al, 2011). However, we could not exclude the possibility that other exon insertions or other clones exist in the porcine SKIP gene.…”

“…This further confirmed our conclusion that SKIP gene is a positional and biological candidate gene for these carcass and growth traits. The SKIP gene had been assigned to SSC12 q1.3 (Xiong et al, 2011). The SSC12 region was considered to have QTLs for Backfat thickness at 10th rib, carcass yield (Thomsen, Lee, Rothschild, Malek, & Dekkers, 2004), number of muscle fibers (Wimmers et al, 2006), and ham weight (Milan et al, 2002).…”