Serine/threonine protein phosphatases and regulation of K-Cl cotransport in human erythrocytes.

Content Provider	Semantic Scholar
Author	Bize, Isabel Güvenç, Birol Robb, Aeisha D. Buchbinder, Guido Brugnara, Carlo
Copyright Year	1999
Abstract	Activation of K-Cl cotransport is associated with activation of membrane-bound serine/threonine protein phosphatases (S/T-PPases). We characterize red blood cell S/T-PPases and K-Cl cotransport activity regarding protein phosphatase inhibitors and response to changes in ionic strength and cell size. Protein phosphatase type 1 (PP1) activity is highly sensitive to calyculin A (CalA) but not to okadaic acid (OA). PP2A activity is highly sensitive to CalA and OA. CalA completely inhibits K-Cl cotransport activity, whereas OA partially inhibits K-Cl cotransport. Membrane PP1 and membrane PP2A activities are elevated in cells suspended in hypotonic solutions, where K-Cl cotransport is elevated. Increases in membrane PP1 activity (62 ± 10% per 100 meq/l) result from decreases in intracellular ionic strength and correlate with increases in K-Cl cotransport activity (54 ± 10% per 100 meq/l). Increases in membrane PP2A activity (270 ± 77% per 100 mosM) result from volume increases and also correlate with increases in K-Cl cotransport activity (420 ± 47% per 100 mosM). The characteristics of membrane-associated PP1 and PP2A are consistent with a role for both phosphatases in K-Cl cotransport activation in human erythrocytes.
Starting Page	C926
Ending Page	C936
Page Count	1
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://ajpcell.physiology.org/content/ajpcell/277/5/c926.full.pdf
PubMed reference number	29590860v1
Alternate Webpage(s)	https://doi.org/10.1152/ajpcell.1999.277.5.C926
DOI	10.1152/ajpcell.1999.277.5.c926
Journal	American journal of physiology. Cell physiology
Volume Number	277
Issue Number	5
Language	English
Access Restriction	Open
Subject Keyword	Erythrocytes Hypotonic Solutions Ionic Strength Milliequivalent per Liter Okadaic Acid Phosphoric Monoester Hydrolases Protein Phosphatase 2A Sodium Potassium Chloride Symporter Inhibitors Threonine Tissue membrane calyculin A milliequivalent (meq)
Content Type	Text
Resource Type	Article