Adenovirus vector E4 gene regulates connexin 40 and 43 expression in endothelial cells via PKA and PI3K signal pathways.
Connexins (Cxs) provide a means for intercellular communication and play important roles in the pathophysiology of vascular cardiac diseases. Infection of endothelial cells (ECs) with first-generation E1/E3-deleted E4+ adenovirus (AdE4+) selectively modulates the survival and angiogenic potential of ECs by as of yet unrecognized mechanisms. We show here that AdE4+ vectors potentiate Cx expression in ECs in vitro and in mouse heart tissue. Infection of ECs with AdE4+, but not AdE4-, resulted in a time- and dose-dependent induction of junctional Cx40 expression and suppression of Cx43 protein and mRNA expression. Treatment of ECs with PKA inhibitor H89 or PI3K inhibitor LY294002 prevented the AdE4+-mediated regulation of Cx40 and Cx43 that was associated with diminished AdE4+-mediated survival of ECs. Moreover, both PKA activity and cAMP-response element (CRE)-binding activity were enhanced by treatment of ECs with AdE4+. However, there is no causal evidence of a cross-talk between the 2 modulatory pathways, PKA and PI3K. Remarkably, Cx40 immunostaining was markedly increased and Cx43 was decreased in the heart tissue of mice treated with intra-tracheal AdE4+. Taken together, these results suggest that AdE4+ may play an important role in the regulation of Cx expression in ECs, and that these effects are mediated by both the PKA/CREB and PI3K signaling pathways.
Zhang
Fan
F
Department of Genetic Medicine, Belfer Gene Therapy Core Facility of Weill Medical of Cornell University, New York, NY 10021, USA.
Cheng
Joseph
J
Lam
George
G
Jin
David K
DK
Vincent
Loïc
L
Hackett
Neil R
NR
Wang
Shiyang
S
Young
Lauren M
LM
Hempstead
Barbara
B
Crystal
Ronald G
RG
Rafii
Shahin
S
D000256:Adenoviridae / Q000235:genetics*; D017504:Adenovirus E4 Proteins / Q000235:genetics*; D000818:Animals; D018031:Connexin 43 / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D017630:Connexins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D017362:Cyclic AMP Response Element-Binding Protein / Q000502:physiology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism* / Q000502:physiology; D042783:Endothelial Cells / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D044385:GTP-Binding Protein alpha Subunits / Q000378:metabolism; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006801:Humans; D051379:Mice; D009206:Myocardium / Q000378:metabolism; D037342:Pertussis Toxin / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D000097003:Gap Junction alpha-5 Protein
D017504:Adenovirus E4 Proteins; D018031:Connexin 43; D017630:Connexins; D017362:Cyclic AMP Response Element-Binding Protein; D017868:Cyclic AMP-Dependent Protein Kinases; D044385:GTP-Binding Protein alpha Subunits; D037342:Pertussis Toxin; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger; D000097003:Gap Junction alpha-5 Protein