Isotocin controls ion regulation through regulating ionocyte progenitor differentiation and proliferation

Cell Mol Life Sci. 2011 Aug;68(16):2797-809. doi: 10.1007/s00018-010-0593-2. Epub 2010 Nov 24.

Abstract

The present study using zebrafish as a model explores the role of isotocin, a homolog of oxytocin, in controlling ion regulatory mechanisms. Double-deionized water treatment for 24 h significantly stimulated isotocin mRNA expression in zebrafish embryos. Whole-body Cl(-), Ca(2+), and Na(+) contents, mRNA expressions of ion transporters and ionocyte-differentiation related transcription factors, and the number of skin ionocytes decreased in isotocin morphants. In contrast, overexpression of isotocin caused an increase in ionocyte numbers. Isotocin morpholino caused significant suppression of foxi3a mRNA expression, while isotocin cRNA stimulated foxi3a mRNA expressions at the tail-bud stage of zebrafish embryos. The density of P63 (an epidermal stem cell marker)-positive cells was downregulated by isotocin morpholinos and was upregulated by isotocin cRNA. Taken together, isotocin stimulates the proliferation of epidermal stem cells and differentiation of ionocyte progenitors by regulating the P63 and Foxi3a transcription factors, consequently enhancing the functional activities of ionocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation
  • Cell Proliferation
  • Down-Regulation
  • Embryo, Nonmammalian / metabolism
  • Forkhead Transcription Factors / genetics
  • Forkhead Transcription Factors / metabolism
  • Ion Transport
  • Ions / metabolism*
  • Oxytocin / analogs & derivatives*
  • Oxytocin / genetics
  • Oxytocin / metabolism
  • Oxytocin / physiology
  • Phosphoproteins / metabolism
  • Stem Cells / cytology*
  • Stem Cells / metabolism
  • Trans-Activators / metabolism
  • Zebrafish / embryology
  • Zebrafish / metabolism
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / metabolism*
  • Zebrafish Proteins / physiology

Substances

  • Forkhead Transcription Factors
  • Ions
  • Phosphoproteins
  • Tp63 protein, zebrafish
  • Trans-Activators
  • Zebrafish Proteins
  • foxi3a protein, zebrafish
  • Oxytocin
  • isotocin