JCB logo
Accuri Cytometers
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
Published 25 April 2005. doi:10.1083/jcb.200412145
The Rockefeller University Press, 0021-9525 $8.00
JCB, Volume 169, Number 2, 321-329
This Article
Right arrow Full Text
Right arrow Full Text (PDF, 1290K)
Right arrow PPT slides of all figures
Right arrow Supplemental Material Index
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JCB
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Patel, H.
Right arrow Articles by Barber, D. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Patel, H.
Right arrow Articles by Barber, D. L.
Right arrowPubmed/NCBI databases
*Gene
*Substance via MeSH
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Facebook   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Article

A developmentally regulated Na-H exchanger in Dictyostelium discoideum is necessary for cell polarity during chemotaxis



Hitesh Patel and Diane L. Barber

Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143

Correspondence to Diane L. Barber: barber{at}itsa.ucsf.edu

Increased intracellular H+ efflux is speculated to be an evolutionarily conserved mechanism necessary for rapid assembly of cytoskeletal filaments and for morphological polarity during cell motility. In Dictyostelium discoideum, increased intracellular pH through undefined transport mechanisms plays a key role in directed cell movement. We report that a developmentally regulated Na-H exchanger in Dictyostelium discoideum (DdNHE1) localizes to the leading edge of polarized cells and is necessary for intracellular pH homeostasis and for efficient chemotaxis. Starved DdNHE1-null cells (Ddnhe1–) differentiate, and in response to the chemoattractant cAMP they retain directional sensing; however, they cannot attain a polarized morphology, but instead extend mislocalized pseudopodia around the cell and exhibit decreased velocity. Consistent with impaired polarity, in response to chemoattractant, Ddnhe1– cells lack a leading edge localization of F-actin and have significantly attenuated de novo F-actin polymerization but increased abundance of membrane-associated phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3). These findings indicate that during chemotaxis DdNHE1 is necessary for establishing the kinetics of actin polymerization and PI(3,4,5)P3 production and for attaining a polarized phenotype.

Abbreviations used in this paper: CRAC, cytosolic regulator of adenylyl cyclase; PH, pleckstrin homology; pHi, intracellular pH; PI3, phosphatidylinositol 3; PI(3,4,5)P3, phosphatidylinositol 3,4,5-trisphosphate.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents