Targeted disruption of the basic Krüppel-like factor gene (Klf3) reveals a role in adipogenesis.

Krüppel-like factors (KLFs) recognize CACCC and GC-rich sequences in gene regulatory elements. Here, we describe the disruption of the murine basic Krüppel-like factor gene (Bklf or Klf3). Klf3 knockout mice have less white adipose tissue, and their fat pads contain smaller and fewer cells.

Human KLF17 is a new member of the Sp/KLF family of transcription factors.

The Sp/KLF transcription factors perform a variety of biological functions, but are related in that they bind GC-box and CACCC-box sequences in DNA via a highly conserved DNA-binding domain. A database homology search, using the zinc finger DNA-binding domain characteristic of the family, has identified human KLF17 as a new family member that is most closely related to KLFs 1-8 and 12. KLF17 appears to be the human orthologue of the previously reported mouse gene, zinc finger protein 393 (Zfp393), although it has diverged significantly.

KAI1 promoter activity is dependent on p53, junB and AP2: evidence for a possible mechanism underlying loss of KAI1 expression in cancer cells.

A molecular mechanism to explain reduced KAI1 expression in invasive and metastatic tumour cells remains elusive. In this report, we extend an earlier study in bladder cells to confirm that a 76 bp region of the KAI1 promoter (residues -922 to -847), with binding motifs for p53, AP1 and AP2, is required for high level activity of a KAI1 reporter in prostate cancer cell lines. Gel shift and supershift experiments supported binding of p53, junB and heterodimers of AP2alpha/AP2gamma or AP2beta/AP2gamma to this sequence.

Pentaprobe: a comprehensive sequence for the one-step detection of DNA-binding activities.

The rapid increase in the number of novel proteins identified in genome projects necessitates simple and rapid methods for assigning function. We describe a strategy for determining whether novel proteins possess typical sequence-specific DNA-binding activity. Many proteins bind recognition sequences of 5 bp or less.

CCHX zinc finger derivatives retain the ability to bind Zn(II) and mediate protein-DNA interactions.

Classical (CCHH) zinc fingers are among the most common protein domains found in eukaryotes. They function as molecular recognition elements that mediate specific contact with DNA, RNA, or other proteins and are composed of a betabetaalpha fold surrounding a single zinc ion that is ligated by two cysteine and two histidine residues. In a number of variant zinc fingers, the final histidine is not conserved, and in other unrelated zinc binding domains, residues such as aspartate can function as zinc ligands.

Identification of regulatory regions within the KAI1 promoter: a role for binding of AP1, AP2 and p53.

The mechanism underlying loss of KAI1 gene expression in invasive and metastatic tumour cells is unknown. A possible scenario could involve altered expression or function of protein factors normally involved in regulating KAI1 transcription. To explore this possibility, we have initiated a study to characterise regulatory elements of the KAI1 promoter, using as a model, two bladder cancer cell lines (BL13 and HT1376) expressing high levels of endogenous KAI1 messenger RNA (mRNA).