Plasma Membrane Calcium ATPase (PMCA) plays a critical role in transporting Ca<sup>2+</sup> out of the cytosol across the plasma membrane. Here, a full-length cDNA sequence of plasma membrane Ca<sup>...Plasma Membrane Calcium ATPase (PMCA) plays a critical role in transporting Ca<sup>2+</sup> out of the cytosol across the plasma membrane. Here, a full-length cDNA sequence of plasma membrane Ca<sup>2+</sup>-ATPase gene was isolated from the gill of <em>Hyriopsis cumingii</em> (HcPMCA) by using SMART RACE technique. The entire cDNA was 5230 bp, including a 417-bp 5'-UTR, a 3588-bp ORF and a 1225-bp 3'-UTR, encoding a 1195-amino acid protein, and no putative signal peptide was predicted. Compared with PMCA homologs from seawater mollusks, HcPMCA had high similarity with them in both sequence and structure. Tissue-specific expression analysis revealed that HcPMCA mRNA was detected in all the sampled tissues, but was prominently expressed in the gill and mantle. When exposed to a serie of increasing Ca<sup>2+</sup> that lasted for 7 days, the mRNA expression of HcPMCA in the mantle was slightly downregulated, but peaked at 60 mg/L. Moreover, the temporal expression of HcPMCA transcripts in the mantle after 60 mg/L Ca<sup>2+</sup> exposure was shown to be bell-shaped, which was slightly downregulated at 24 h, but upregulated from 24 h to 48 h post-treatment, peaking at 48 h. The result of present study provides useful information for further studies on function and regulation mechanism of HcPMCA gene.展开更多
文摘Plasma Membrane Calcium ATPase (PMCA) plays a critical role in transporting Ca<sup>2+</sup> out of the cytosol across the plasma membrane. Here, a full-length cDNA sequence of plasma membrane Ca<sup>2+</sup>-ATPase gene was isolated from the gill of <em>Hyriopsis cumingii</em> (HcPMCA) by using SMART RACE technique. The entire cDNA was 5230 bp, including a 417-bp 5'-UTR, a 3588-bp ORF and a 1225-bp 3'-UTR, encoding a 1195-amino acid protein, and no putative signal peptide was predicted. Compared with PMCA homologs from seawater mollusks, HcPMCA had high similarity with them in both sequence and structure. Tissue-specific expression analysis revealed that HcPMCA mRNA was detected in all the sampled tissues, but was prominently expressed in the gill and mantle. When exposed to a serie of increasing Ca<sup>2+</sup> that lasted for 7 days, the mRNA expression of HcPMCA in the mantle was slightly downregulated, but peaked at 60 mg/L. Moreover, the temporal expression of HcPMCA transcripts in the mantle after 60 mg/L Ca<sup>2+</sup> exposure was shown to be bell-shaped, which was slightly downregulated at 24 h, but upregulated from 24 h to 48 h post-treatment, peaking at 48 h. The result of present study provides useful information for further studies on function and regulation mechanism of HcPMCA gene.
