Page 2 - H. Cell signaling

[H. Cell signaling-1]

Arginase II down regulation recovers Ca2+/CaMKII-Akt-eNOS

signaling and vascular homeostasis in p32 over expressed

Bon Hyeock Koo¹, Sung Woo Ryoo¹˙*

¹BIT medical-convergence, Kangwon national university, chun cheon 24341, Korea

Maintaining vascular homeostasis is important physiologically for vascular systems. Many studies shown lots of
methods to alleviates vascular dysfunction and have been studied until now. We focus on intracellular Ca2+ signaling
between mitochondria and cytosol which is regulated by mitochondrial p32 and their mechanism is important for

vascular homeostasis. p32 is known as HABP1, gC1qR, C1qbp which known to have a variety of functions and is

predominantly placed in mitochondria because p32 has mitochondrial targeting sequence contained in 73N-
terminal amino acid. Especially among the p32 functions, our previous research is found that p32 is possible to
uptake from cytosol to mitochondria. To find the exactly p32 function, we over expressed the p32 by transfection

of p32 cDNA tagged flag in adenovirus and p32 dominantly expressed in not only mitochondria but also
endoplasmic reticulum (ER). Over expressed p32 also has a Ca2+ uptake function from cytosol to mitochondria and

ER which caused reduction of CaMKII/Akt/eNOS signaling axis and NO production by decreasing the cytosolic Ca2+
level. However, our study found that arginase II down regulation induces to decrease over expressed p32 levels and

then, reduced p32 level is activation of CaMKII/eNOS signaling again.