Abstract:Four members,jph1a,jphb, jph2 and jph3,of the junctophilin family were isolated and characterized in Megalobrama amblycephala,an important freshwater fish. The jph1a,jph1b, jph2 and jph3 cDNA contained an open reading frame (ORF) of 2 031 bp,2 016 bp,2 358 bp and 2 361 bp,encoding 676 aa,671 aa,785 aa and 786 aa,respectively. Structure analysis showed that all the M. amblycephala jphs consisted of 5 exons and 4 introns,which is consistent with that of other species. All the 4 M. amblycephala Jph proteins were composed of 8 MORN motifs and a TM motif,and multiple sequence alignment showed that these MORN and TM domains were highly conserved. Based on quantitative real-time PCR (qRT-PCR), the 4 jph genes exhibited tissue-specific expression,of which jph1a,jph1b,and jph2 were abundant in the muscle and heart,and jph3 was mainly expressed in the heart,blood and brain. During early development,the jph1a,jph1b, jph2 and jph3 mRNA levels peaked at the gastrula stage,heartbeat stage and 25 dph (days post hatching),respectively. These results suggest that Jphs may play important roles in some tissues such as the heart and muscle,and may have more extensive functions in fish compared to mammals.