ZFIN ID: ZDB-PUB-101011-40
Two different unique cardiac isoforms of protein 4.1R in zebrafish, Danio rerio, and insights into their cardiac functions as related to their unique structures
Murata, K., Nunomura, W., Takakuwa, Y., and Cherr, G.N.
Date: 2010
Source: Development, growth & differentiation   52(7): 591-602 (Journal)
Registered Authors:
Keywords: atrium and ventricle, FERM domain, protein 4.1R, spectrin actin binding domain, Zebrafish (Danio Rerio)
MeSH Terms:
  • Animals
  • Blotting, Western
  • Cytoskeletal Proteins/chemistry*
  • Cytoskeletal Proteins/genetics
  • Cytoskeletal Proteins/metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Gene Expression Profiling
  • Immunohistochemistry
  • Membrane Proteins/chemistry*
  • Membrane Proteins/genetics
  • Membrane Proteins/metabolism*
  • Myocardium/metabolism*
  • Protein Isoforms/genetics
  • Protein Isoforms/metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Zebrafish/genetics
  • Zebrafish/metabolism*
  • Zebrafish Proteins/chemistry*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 20887560 Full text @ Dev. Growth Diff.
Protein 4.1R (4.1R) has been identified as the major component of the human erythrocyte membrane skeleton. The members of the protein 4.1 gene family are expressed in a tissue-specific alternative splicing manner that increases their functions in each tissue; however, the exact roles of cardiac 4.1R in the developing myocardium are poorly understood. In zebrafish (ZF), we identified two heart-specific 4.1R isoforms, ZF4.1RH2 and ZF4.1RH3, encoding N-terminal 30 kDa (FERM) domain and spectrin-actin binding domain (SABD) and C-terminal domain (CTD), separately. Applying immunohistochemistry using specific antibodies for 30 kDa domain and CTD separately, the gene product of ZF4.1RH2 and ZF4.1RH3 appeared only in the ventricle and in the atrium, respectively, in mature hearts. During embryogenesis, both gene expressions are expressed starting 24 h post-fertilization (hpf). Following whole-mount in situ hybridization, ZF4.1RH3 gene expression was detected in the atrium of 37 hpf embryos. These results indicate that the gene product of ZF4.1RH3 is essential for normal morphological shape of the developing heart and to support the repetitive cycles of its muscle contraction and relaxation.