ZFIN ID: ZDB-PUB-101011-19
Molecular and Functional Analyses of Aspolin, a Fish-Specific Protein Extremely Rich in Aspartic Acid
Kinoshita, S., Katsumi, E., Yamamoto, H., Takeuchi, K., and Watabe, S.
Date: 2011
Source: Marine biotechnology (New York, N.Y.)   13(3): 517-526 (Journal)
Registered Authors: Kinoshita, Shigeharu, Watabe, Shugo
Keywords: Aspolin, Molecular evolution, Histidine-rich calcium binding protein (HRC), Sarcoplasmic reticulum, Muscle, Fish
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Western
  • Calcium-Binding Proteins/genetics*
  • Calcium-Binding Proteins/metabolism*
  • Cloning, Molecular
  • Cluster Analysis
  • DNA Primers/genetics
  • DNA, Complementary/genetics
  • Gene Components
  • Gene Knockdown Techniques
  • Immunohistochemistry
  • In Situ Hybridization
  • Molecular Sequence Data
  • Muscle Proteins/genetics*
  • Muscle Proteins/metabolism*
  • Muscle, Skeletal/metabolism
  • Phylogeny*
  • Physical Chromosome Mapping
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Zebrafish*
PubMed: 20878432 Full text @ Mar. Biotechnol.
Aspolin is a muscular protein having unique structural characteristics where the most part of its primary structure is occupied by aspartic acid. Aspolin has been found exceptionally in fish muscle, suggesting its specific role in this tissue. However, biological functions of aspolin have remained unknown. In the present study, we cloned full-length cDNAs encoding zebrafish Danio rerio aspolins 1 and 2, revealed their genomic organization, and examined in vivo function using knockdown techniques. Genomic analysis clearly showed that aspolin is a paralog of the histidine-rich calcium binding protein gene, which encodes a calcium binding protein in sarcoplasmic reticulum (SR). Expression analysis showed that the transcripts and their translated products, aspolins 1 and 2, are distributed in myotomal skeletal muscle, but not in cardiac muscle. Injection of antisense morpholino oligo targeting both aspolins 1 and 2 increased the mRNA levels of calsequestrin 1, another calcium binding protein in SR. These lines of evidence suggest that aspolins regulate calcium concentrations in SR.