A maize zinc-finger protein binds the prolamin box in zein gene promoters and interacts with the basic leucine zipper transcriptional activator Opaque2

ABSTRACT p130 cas (Cas) is a docking protein that contains an SH3 domain and multiple tyrosine residues. p130 cas is located at focal adhesions, is tyrosine phosphorylated in response to integrin stimulation, and is thought to transmit signals, via c-Crk and other proteins, for the remodeling of actin stress fibers and cell movement. In a search for the ligands of the SH3 domain of p130 cas by far-Western screening, we cloned a novel protein named CIZ (for Cas-interacting zinc finger protein). CIZ consists of the following: a putative leucine zipper; a serine/threonine-rich region; a proline-rich sequence; five, six, or eight Krüppel-type C2H2 zinc fingers; and the glutamine-alanine repeat. CIZ binds Cas in cells and is located in the nucleus and at focal adhesions. We showed that CIZ is a nucleocytoplasmic shuttling protein, by using the transient interspecies heterokaryon formation assay. In order to search for the targets of CIZ in nucleus, we determined the DNA binding consensus of CIZ as (G/C)AAAAA(A) by cyclic amplification and selection of targets analysis. The consensus-like sequences are found in several promoters of matrix metalloproteinases (MMPs), which are the enzymes used to degrade the extracellular matrix proteins. CIZ binds to a consensus-like sequence in the MMP-1 (collagenase) promoter. Overexpression of CIZ upregulates the transcriptions from MMP-1, MMP-3 (stromelysin), and MMP-7 (matrilysin) promoters, and this transactivation was enhanced in the presence of Cas. Furthermore, the stable overexpression of CIZ promoted the production of MMP-7 in culture medium. In summary, CIZ, a novel zinc finger protein, binds Cas, is a nucleocytoplasmic shuttling protein, and regulates the expression of MMPs.

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Two types of zinc fingers are required for dimerization of the serendipity delta transcriptional activator.

Molecular and Cellular Biology ◽

10.1128/mcb.17.6.3137 ◽

1997 ◽

Vol 17 (6) ◽

pp. 3137-3145 ◽

Cited By ~ 16

Author(s):

F Payre ◽

P Buono ◽

N Vanzo ◽

A Vincent

Keyword(s):

Dna Binding ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Zinc Fingers ◽

Point Mutations ◽

Transcriptional Activator ◽

Consensus Binding Site ◽

Finger Protein ◽

Synergistic Activation ◽

Dna Binding Affinity

The serendipity (sry) delta zinc finger protein controls bicoid gene expression during Drosophila melanogaster oogenesis. In addition, sry delta mutants display various zygotic phenotypes, ranging from abnormal embryogenesis to sex-biased adult lethality. We report here that sry delta is a sequence-specific transcriptional activator. A single sry delta consensus binding site (SDCS), in either orientation, is sufficient to promote transcription activation in cell culture, and multiple SDCSs mediate a strong synergistic activation, reflecting the cooperativity of sry delta binding to DNA. Further, several lines of evidence strongly suggest that sry delta binds to DNA as a dimer. While each of three point mutations located in the third zinc finger of sry delta drastically reduces its DNA binding affinity, a fourth mutation, located in the N-terminal region of the protein, specifically affects the cooperativity of DNA binding. This mutation reveals the functional importance of a putative Cys2/Cys2 zinc finger motif of a novel type, located outside the DNA binding domain. A systematic deletion analysis shows that interaction between this proposed Cys2/Cys2 motif and a classical Cys2/His2 zinc finger mediates homodimerization, which is required for DNA binding cooperativity.

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A non‐tandem CCCH ‐type zinc‐finger protein, IbC3H18, functions as a nuclear transcriptional activator and enhances abiotic stress tolerance in sweet potato

New Phytologist ◽

10.1111/nph.15925 ◽

2019 ◽

Vol 223 (4) ◽

pp. 1918-1936 ◽

Cited By ~ 7

Author(s):

Huan Zhang ◽

Xiaoru Gao ◽

Yuhai Zhi ◽

Xu Li ◽

Qian Zhang ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Sweet Potato ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Abiotic Stress Tolerance ◽

Transcriptional Activator ◽

Finger Protein

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Connecting homocysteine and obesity through pyroptosis, gut microbiome, epigenetics, peroxisome proliferator-activated receptor γ, and zinc finger protein 407

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2018-0037 ◽

2018 ◽

Vol 96 (10) ◽

pp. 971-976 ◽

Cited By ~ 8

Author(s):

Anwesha Laha ◽

Avisek Majumder ◽

Mahavir Singh ◽

Suresh C. Tyagi

Keyword(s):

Zinc Finger ◽

Gut Microbiome ◽

Metabolic Disorders ◽

Zinc Finger Protein ◽

Specific Gene ◽

Peroxisome Proliferator ◽

Gene Promoters ◽

Divalent Metal Ions ◽

Peroxisome Proliferator Activated Receptor ◽

Finger Protein

Although homocysteine (Hcy), a part of the epigenome, contributes to cell death by pyroptosis and decreases peroxisome proliferator-activated receptor γ (PPARγ) levels, the mechanisms are unclear. Hcy is found in high concentrations in the sera of obese individuals, which can elicit an immune response as well by hypermethylating CpG islands of specific gene promoters, a marker of epigenetics. Hcy has also been established to chelate divalent metal ions like Cu2+ and Zn2+, but this role of Hcy has not been established in relationship with obesity. It has been known for a while that PPARγ dysregulation results in various metabolic disorders including glucose and lipid metabolism. Recently, zinc finger protein 407 (Zfp407) is reported to regulate PPARγ target gene expression without affecting PPARγ transcript and protein levels by synergistically working with PPARγ. However, the mechanism(s) of this synergy, as well as other factors contributing to or inhibiting this synergism, have not been proven. This review suggests that Hcy contributes to pyroptosis, changes gut microbiome, and alters PPARγ-dependent mechanism(s) via Zfp407-mediated upregulated adipogenesis and misbalanced fatty acid metabolism, which can predispose to obesity and, consequently, obesity-related metabolic disorders.

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