生醫所107-1專題演講活動，敬邀 臺灣大學醫學院 生物化學暨分子生物學研究所 林敬哲教授進行專題演講。
演講主題為：
Revealing a role of serine protease inhibitor SerpinB2 in senescence
一、 演講時間：107年10月02日(星期二) 下午1:10至3:00
二、 地點：地點：第二教研大樓G區5樓 525教室
三、 參與對象：參與對象：本校教師、生醫所全體師生

Abstract
SerpinB2 is a serine protease inhibitor that is also known as plasminogen activator inhibitor type 2 (PAI-2). It has been well documented that serpinB2 is an inhibitor of urokinase plasminogen activator (uPA) and tissue plasminogen activator (tPA). Interestingly, serpinB2 level is increased in senescent cells and is considered a senescence biomarker. Through mimicking the elevated level of serpinB2 in senescent cells, this study showed the proliferating human fibroblasts were induced into senescence. Senescence induced by serpinB2 did not relate to its extracellular function as inhibition of serpinB2 secretion, exogenous introduced serpinB2, or a serpinB2 mutant that failed to bind to its extracellular target uPA, did not have an effect on senescence. SerpinB2 is a direct downstream target of p53 that is activated through the DNA damage response pathway. It binds to and stabilizes p21 to mediate senescence in a proteasome-independent manner, indicating serpinB2 has a direct role in senescence. Thus, serpinB2 has a unique role in maintaining senescence through stabilizing the p21 protein level.