ZFIN ID: ZDB-PUB-130927-15
Protein Phosphatase 1 beta Paralogs Encode the Zebrafish Myosin Phosphatase Catalytic Subunit
Jayashankar, V., Nguyen, M.J., Carr, B.W., Zheng, D.C., Rosales, J.B., Rosales, J.B., and Weiser, D.C.
Date: 2013
Source: PLoS One   8(9): e75766 (Journal)
Registered Authors: Weiser, Douglas C.
Keywords: none
MeSH Terms:
  • Actin Cytoskeleton/metabolism
  • Amino Acid Sequence
  • Animals
  • Cardiac Myosins/metabolism
  • Catalytic Domain*
  • Gene Expression Regulation, Developmental
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Mice
  • Molecular Sequence Data
  • Myosin Light Chains/metabolism
  • Myosin-Light-Chain Phosphatase/chemistry
  • Myosin-Light-Chain Phosphatase/genetics*
  • Myosin-Light-Chain Phosphatase/metabolism*
  • Phosphorylation
  • Protein Phosphatase 1/chemistry
  • Protein Phosphatase 1/genetics*
  • Protein Phosphatase 1/metabolism*
  • Sequence Homology, Nucleic Acid*
  • Zebrafish/embryology
  • Zebrafish/genetics*
  • Zebrafish/metabolism
PubMed: 24040418 Full text @ PLoS One


The myosin phosphatase is a highly conserved regulator of actomyosin contractility. Zebrafish has emerged as an ideal model system to study the in vivo role of myosin phosphatase in controlling cell contractility, cell movement and epithelial biology. Most work in zebrafish has focused on the regulatory subunit of the myosin phosphatase called Mypt1. In this work, we examined the critical role of Protein Phosphatase 1, PP1, the catalytic subunit of the myosin phosphatase.

Methodology/Principal Findings

We observed that in zebrafish two paralogous genes encoding PP1β, called ppp1cba and ppp1cbb, are both broadly expressed during early development. Furthermore, we found that both gene products interact with Mypt1 and assemble an active myosin phosphatase complex. In addition, expression of this complex results in dephosphorylation of the myosin regulatory light chain and large scale rearrangements of the actin cytoskeleton. Morpholino knock-down of ppp1cba and ppp1cbb results in severe defects in morphogenetic cell movements during gastrulation through loss of myosin phosphatase function.


Our work demonstrates that zebrafish have two genes encoding PP1β, both of which can interact with Mypt1 and assemble an active myosin phosphatase. In addition, both genes are required for convergence and extension during gastrulation and correct dosage of the protein products is required.