Human kallikrein-related peptidase 14 (KLK14) is a new activator component of the KLK proteolytic cascade - Possible function in seminal plasma and skin
Human kallikrein-related peptidase 14 (KLK14) is a new activator component of the KLK proteolytic cascade - Possible function in seminal plasma and skin
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DOI：
10.1074/jbc.m707253200
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发表时间：
2008-02-08
影响因子：
4.8
通讯作者：
Diamandis, Eleftherios P.
中科院分区：
文献类型：
--
作者：
Emami, Nashmil;Diamandis, Eleftherios P.
人激肽释放酶相关肽酶 (KLK) 是一个由 15 种丝氨酸蛋白酶组成的家族，主要因其在各种肿瘤和非肿瘤疾病中的生物标志物用途而闻名。尽管在了解其临床应用方面取得了重大进展，但人们对这一重要酶家族的激活机制知之甚少。新的证据表明 KLK 以逐步的方式被激活，这是蛋白水解级联的一个特征。迄今为止，KLK 级联与精液液化和皮肤脱屑有关。据报道，KLK 家族的许多成员在精浆和/或皮肤中具有活性，表明它们参与常见的蛋白水解级联反应。尤其是 KLK14，其活性很高，最近被认为是参与皮肤脱屑的关键胰蛋白酶样蛋白酶之一。本研究旨在通过以下方式阐明 KLK14 可能的级联介导作用：1) 检查 KLK14 介导的包含 15 个 KLK 激活位点的七肽库的裂解；2) 验证 KLK14 某些候选下游靶标（即前 KLK1、-KLK3 和 -KLK11）的激活。包含 KLK2、-3、-5 和 -11 激活基序的七肽以高 (>= 85%) 的切割效率进行切割。使用全长重组蛋白证实了这些候选物的激活。 Pro-KLK11、-KLK3 和-KLK1 以浓度依赖性方式快速激活。 Pro-KLK3 调节是双向的，因为激活后会通过活性 KLK3 的内部裂解而失活。我们提出了一个假定的级联模型，通过多个 KLK 进行操作。鉴定此类蛋白水解级联的新成员将有助于进一步确定涉及精液/皮肤稳态的机制。
Human kallikrein-related peptidases (KLKs) are a family of 15 serine proteases mainly known for their biomarker utility in various neoplastic and non-neoplastic diseases. Despite significant progress in understanding their clinical application, little is known about the activation mechanism(s) of this important family of enzymes. Emerging evidence indicates that KLKs are activated in a stepwise manner, which is a characteristic of proteolytic cascades. Thus far, KLK cascades have been implicated in semen liquefaction and skin desquamation. Many members of the KLK family have been reported to be active in seminal plasma and/or skin, suggesting their involvement in common proteolytic cascades. KLK14, in particular, is highly active and has recently been proposed as one of the key trypsin-like proteases involved in skin desquamation. This study aims to elucidate a probable cascade-mediated role of KLK14 by 1) examining KLK14-mediated cleavage of a heptapeptide library encompassing activation sites of the 15 KLKs and 2) verifying activation of certain candidate downstream targets of KLK14 (i.e. pro-KLK1, -KLK3, and -KLK11). Heptapeptides encompassing activation motifs of KLK2, -3, -5, and -11 were cleaved with a high (>= 85%) cleavage efficiency. Activation of these candidates was confirmed using full-length recombinant proteins. Pro-KLK11, -KLK3, and -KLK1 were rapidly activated in a concentration-dependent manner. Pro-KLK3 regulation was bidirectional because activation was followed by inactivation via internal cleavage of active KLK3. We are proposing a putative cascade model, operating through multiple KLKs. Identification of novel members of such proteolytic cascades will aid in further defining mechanisms involved in seminal/skin homeostasis.