Annexin A2 interactions with Rab14 in alveolar type II cells.
Annexin A2, a calcium-dependent phospholipid-binding protein, is abundantly expressed in alveolar type II cells where it plays a role in lung surfactant secretion. Nevertheless, little is known about the details of its cellular pathways. To identify annexin A2-regulated or associated proteins, we silenced endogenous annexin A2 expression in rat alveolar type II cells by RNA interference and assessed the change of the cellular transcriptome by DNA microarray analysis. The loss of annexin A2 resulted in the change of 61 genes. Thirteen of the selected genes (11 down-regulated and 2 up-regulated genes) were validated by real time quantitative PCR. When the loss of rat annexin A2 was rescued by overexpressing EGFP-tagged human annexin A2, six of seven selected targets returned to their normal expression level, indicating that these genes are indeed annexin A2-associated targets. One of the targets, Rab14, co-immunoprecipitated with annexin A2. Rab14 also co-localized in part with annexin A2 and lamellar bodies in alveolar type II cells. The silencing of Rab14 resulted in a decrease in surfactant secretion, suggesting that Rab14 may play a role in surfactant secretion.
Gou
Deming
D
Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
Mishra
Amarjit
A
Weng
Tingting
T
Su
Lijing
L
Chintagari
Narendranath Reddy
NR
Wang
Zhixin
Z
Zhang
Honghao
H
Gao
Li
L
Wang
Pengcheng
P
Stricker
Heidi M
HM
Liu
Lin
L
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D017306:Annexin A2 / Q000235:genetics / Q000378:metabolism*; D001011:Aorta / Q000378:metabolism*; D002478:Cells, Cultured; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D047468:Immunoprecipitation; D008168:Lung / Q000378:metabolism; D011485:Protein Binding; D034622:RNA Interference; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014158:Transcription, Genetic / Q000235:genetics; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
D017306:Annexin A2; C494592:Rab14 protein, rat; D020691:rab GTP-Binding Proteins