Structure of the human TIMP-3 gene and its cell cycle-regulated promoter

Abstract

The gene encoding tissue inhibitor of metalloproteinases-3 (TIMP-3) is regulated during development, mitogenic stimulation and normal cell cycle progression. The TIMP-3 gene is structurally altered or deregulated in certain diseases of the eye and in tumour cells. A detailed knowledge of the TIMP-3 gene and its regulatory elements is therefore of paramount importance to understand its role in development, cell cycle progression and disease. In this study, we present the complete structure of the human TIMP-3 gene. We show that TIMP-3 is a TATA-less gene, which initiates transcription at one major site, is composed of five exons and four introns spanning a region of approximately 30 kb, and gives rise to three distinct mRNAs, presumably due to the usage of alternative polyadenylation signals. Using somatic cell hybrids the TIMP-3 locus was mapped to chromosomal location 22q13.1 We also show that the TIMP-3 5' flanking region is sufficient to confer both high basal level expression in growing cells and cell cycle regulation in serum-stimulated cells. While the first 112 bases of the promoter, which harbour multiple Sp1 sites, were found to suffice for high basal level activity, the adjacent region spanning positions -463 and -112 was found to be a major determinant of serum inducibility. These results provide an important basis for further investigations addressing the role of TIMP-3 in physiological processes and pathological conditions.

Myocardial Matrix Remodeling and the Matrix Metalloproteinases: Influence on Cardiac Form and Function

“…Furthermore, exposure to phorbol esters, which in time would increase protein kinase C activity, increased TIMP-1 transcriptional activity, but TIMP-2 expression remained unchanged from basal levels (86,151). TIMP-3 appears to be devoid of a TATA sequence, but contains multiple Sp1 sites (10,498). In murine fibroblast systems, exposure to the steroid dexamethasone actually induced TIMP-3 expression, whereas TIMP-1 levels were suppressed (216).…”

Tissue Inhibitor of Metalloproteinases-1, −2, and −3 Polymorphisms in a White Population With Intracranial Aneurysms

“…The first 112 bp of the promoter harbors multiple Sp1 binding sites, and a potential NF I site is located between Ϫ235 and Ϫ248. 35 This region has been shown to be elementary for TIMP-3 basal activity and serum inducibility. 35 Nevertheless, we analyzed only a part of the entire promoter region and did not screen for posttranslational modifications or epigenetic effects that might influence the expression of a gene.…”

P14ARF inhibits human glioblastoma–induced angiogenesis by upregulating the expression of TIMP3

“…The human TIMP3 upstream sequence (-390 to +1) contains a number of binding motifs for known transcription factors, including SP1 and potential NF1 and c/EBP sites (23). Because SP1 has 4 binding sites located in the region (-112 and +1) proximal to the transcription start site, we examined whether SP1 is the downstream mediator of P14ARF's effects on TIMP3.…”