University of East Anglia, Norwich, UK.
Biochem J. 2010 Apr 14;427(3):391-400. doi: 10.1042/BJ20091798.
MMP-28 (epilysin) is a recently cloned member of the MMP (matrix metalloproteinase) family. It is highly expressed in the skin by keratinocytes, the developing and regenerating nervous system and a number of other normal human tissues, as well as a number of carcinomas. The MMP28 promoter has previously been cloned and characterized identifying a conserved GT-box that binds Sp1/Sp3 (specificity proteins 1 and 3) proteins and is essential for the basal expression of the gene. The present study demonstrates that MMP28 expression is induced by HDAC (histone deacetylase) inhibitors and that this effect is mediated through the GT-box. Transient transfection assays have shown that the induction of MMP28 expression by the HDAC inhibitior TSA (trichostatin A) is mediated via Sp1 at the GT-box. Immunoprecipitation experiments have shown that the acetylation of Sp1 and Sp3 is increased by TSA treatment; however, no effect on DNA binding was observed. Histone acetyltransferases such as p300 and P/CAF [p300/CREB (cAMP-response-element-binding protein)-binding protein-associated factor] increased induction of the MMP28 promoter by Sp1. Knockdown of HDAC1 using siRNA (small interfering RNA) also induces the MMP28 promoter. Oligonucleotide pulldown identified STRAP (serine/threonine kinase receptor-associated protein) as a further protein recruited to the MMP28 promoter and acting functionally with Sp1.
MMP-28（epilysin）是基质金属蛋白酶（MMP）家族中最近克隆的成员。它在皮肤的角质形成细胞、发育和再生的神经系统以及许多其他正常的人体组织中高度表达，也在许多癌中表达。MMP28 启动子先前已被克隆并进行了特征鉴定，确定了一个保守的 GT 盒，该盒与 Sp1/Sp3（特异性蛋白 1 和 3）蛋白结合，是基因基础表达所必需的。本研究表明，HDAC（组蛋白去乙酰化酶）抑制剂诱导 MMP28 表达，而这种效应是通过 GT 盒介导的。瞬时转染实验表明，HDAC 抑制剂 TSA（曲古抑菌素 A）诱导 MMP28 表达是通过 GT 盒上的 Sp1 介导的。免疫沉淀实验表明，TSA 处理后 Sp1 和 Sp3 的乙酰化增加，但未观察到 DNA 结合的影响。组蛋白乙酰转移酶，如 p300 和 P/CAF（p300/CREB（环磷酸腺苷反应元件结合蛋白）结合蛋白相关因子），增加了 Sp1 对 MMP28 启动子的诱导。使用 siRNA（小干扰 RNA）敲低 HDAC1 也会诱导 MMP28 启动子。寡核苷酸下拉鉴定出 STRAP（丝氨酸/苏氨酸激酶受体相关蛋白）是另一种被招募到 MMP28 启动子上并与 Sp1 发挥功能的蛋白。
