Affordable Access

deepdyve-link
Publisher Website

The Ca2+/H+ antiporter TMEM165 expression, localization in the developing, lactating and involuting mammary gland parallels the secretory pathway Ca2+ ATPase (SPCA1)

Authors
  • Reinhardt, Timothy A.
  • Lippolis, John D.
  • Sacco, Randy E.1, 2, 3
  • 1 Ruminant Diseases and Immunology Research Unit
  • 2 USDA/ARS
  • 3 National Animal Disease Center
Type
Published Article
Journal
Biochemical and Biophysical Research Communications
Publication Date
Jan 01, 2014
Volume
445
Issue
2
Pages
417–421
Identifiers
DOI: 10.1152/ajpcell.00330.2013
Source
Elsevier
Keywords
License
Unknown

Abstract

Plasma membrane Ca2+-ATPase 2 (PMCA2) knockout mice showed that ∼60% of calcium in milk is transported across the mammary cells apical membrane by PMCA2. The remaining milk calcium is thought to arrive via the secretory pathway through the actions of secretory pathway Ca2+-ATPase’s 1 and/or 2 (SPCA1 and 2). However, another secretory pathway calcium transporter was recently described. The question becomes whether this Golgi Ca2+/H+ antiporter (TMEM165) is expressed sufficiently in the Golgi of lactating mammary tissue to be a relevant contributor to secretory pathway mammary calcium transport. TMEM165 shows marked expression on day one of lactation when compared to timepoints prepartum. At peak lactation TMEM165 expression was 25 times greater than that of early pregnancy. Forced cessation of lactation resulted in a rapid ∼50% decline in TMEM165 expression at 24h of involution and TMEM165 expression declined 95% at 96h involution. It is clear that the timing, magnitude of TMEM165 expression and its Golgi location supports a role for this Golgi Ca2+/H+ antiporter as a contributor to mammary Golgi calcium transport needs, in addition to the better-characterized roles of SPCA1&2.

Report this publication

Statistics

Seen <100 times