Journal
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Volume 329, Issue 1, Pages 6-10Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.bbrc.2005.01.091
Keywords
PI3K-C2 alpha; alpha-isoform of class II phosphoinositide 3-kinase; C2 domain; CHO-IR cells; Chinese hamster ovary cells expressing human insulin receptors; apoptotic cell death; DNA fragmentation; nuclear condensation; apoptotic body; survival factor
Categories
Ask authors/readers for more resources
Phosphoinositide 3-kinases (PI3Ks) have known to be key enzymes activating intracellular signaling molecules when a number of growth factors bind to their cell Surface receptors. PI3Ks are divided into three classes (I, II, and III) and enzymes of each class have different tissue-specificities and physiological functions. Class II PI3Ks consist of three isoforms (alpha, beta, gamma). Although the alpha-isoform (PI3K-C2alpha) is considered ubiquitous and preferentially activated by insulin rather than the beta-isoform, the physiological significance of PI3K-C2alpha is poorly understood. The present study aimed to determine whether PI3K-C2alpha is associated with the suppression of apoptotic cell death. Different sense- and antisense oligonucleotides (ODNs) were synthesized based on the sequence of C2 domain of PI3K-C2alpha gene. Transfection of CHO-IR cells with two different antisense ODNs clearly reduced the protein content as well as mRNA levels of PI3K-C2alpha whereas neither the nonspecific mock- nor- sense ODNs affected. The decrease of PI3K-C2alpha gene expression was paralleled by cellular changes indicating apoptotic cell death such as nuclear condensation, formation of apoptotic bodies, and DNA fragmentation. PI3K-C2alpha mRNA levels were also reduced when cells were incubated in growth factor-deficient medium. Supplementing growth factors (serum or insulin) into medium lead to an increase of PI3K-C2alpha. mRNA levels. This finding strongly Suggests that PI3K-C2alpha is a crucial survival factor. (C) 2005 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available