Integration of a two-phase partition method into proteomics research on rat liver plasma membrane proteins.
To comprehensively identify proteins of the rat liver plasma membrane (PM), we have adopted a proteomics strategy that utilizes sucrose density centrifugation in conjunction with aqueous two-phase partition for plasma membrane isolation, followed by SDS-PAGE, mass spectrometry and bioinformatics. Western blot analysis showed that this method results in highly purified plasma membrane fractions, which is a key to successful plasma membrane proteomics. The PM proteins were separated by SDS-PAGE and digested with trypsin. Through nano-ESI-LC MS/MS analysis we identified 428 rat liver membrane proteins, of which 304 had a gene ontology (GO) annotation indicating a cellular component, and 204 (67%) of the latter were known integral membrane proteins or membrane-associated proteins. In addition to proteins known to be associated with the plasma membrane, several hypothetical proteins have also been identified. This study not only provides a tool to study plasma membrane proteins with low levels of contamination, but also provides a data set for proteins of high to moderate abundance in rat liver plasma membranes, thus allowing for more comprehensive characterization of membrane proteins and a better understanding of membrane dynamics.
Cao
Rui
R
Key Laboratory of Protein Chemistry and Developmental Biology of Education Committee, College of Life Sciences, Hunan Normal University, Changsha, People's Republic of China.
Li
Xuanwen
X
Liu
Zhen
Z
Peng
Xia
X
Hu
Weijun
W
Wang
Xianchun
X
Chen
Ping
P
Xie
Jingyun
J
Liang
Songping
S
D000818:Animals; D002462:Cell Membrane / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D005786:Gene Expression Regulation; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D051381:Rats; D015398:Signal Transduction / Q000502:physiology
D008565:Membrane Proteins