Role of the Putative Zinc Finger Domain ofSaccharomyces cerevisiaeDNA Polymerase ε in DNA Replication and the S/M Checkpoint Pathway

Abstract Ho endonuclease is a LAGLIDADG homing endonuclease that initiates mating-type interconversion in yeast. Ho is encoded by a free-standing gene but shows 50% primary sequence similarity to the intein (protein-intron encoded) PI-SceI. Ho is unique among LAGLIDADG endonucleases in having a 120-residue C-terminal putative zinc finger domain. The crystal structure of PI-SceI revealed a bipartite enzyme with a protein-splicing domain (Hint) and intervening endonuclease domain. We made a homology model for Ho on the basis of the PI-SceI structure and performed mutational analysis of putative critical residues, using a mating-type switch as a bioassay for activity and GFP-fusion proteins to detect nuclear localization. We found that residues of the N-terminal sequence of the Hint domain are important for Ho activity, in particular the DNA recognition region. C-terminal residues of the Hint domain are dispensable for Ho activity; however, the C-terminal putative zinc finger domain is essential. Mutational analysis indicated that residues in Ho that are conserved relative to catalytic, active-site residues in PI-SceI and other related homing endonucleases are essential for Ho activity. Our results indicate that in addition to the conserved catalytic residues, Hint domain residues and the zinc finger domain have evolved a critical role in Ho activity.

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Growth factor-induced tyrosine phosphorylation of Hrs, a novel 115-kilodalton protein with a structurally conserved putative zinc finger domain.

Molecular and Cellular Biology ◽

10.1128/mcb.15.11.6213 ◽

1995 ◽

Vol 15 (11) ◽

pp. 6213-6221 ◽

Cited By ~ 111

Author(s):

M Komada ◽

N Kitamura

Keyword(s):

Amino Acid ◽

Growth Factor ◽

Hepatocyte Growth Factor ◽

Tyrosine Phosphorylation ◽

Zinc Finger ◽

Amino Acid Sequences ◽

Zinc Finger Domain ◽

Rich Region ◽

Putative Zinc Finger ◽

Hepatocyte Growth

The activation of growth factor receptor tyrosine kinases leads to tyrosine phosphorylation of many intracellular proteins which are thought to play crucial roles in growth factor signaling pathways. We previously showed that tyrosine phosphorylation of a 115-kDa protein is rapidly induced in cells treated with hepatocyte growth factor. To clarify the structure and possible function of the 115-kDa protein (designated Hrs for hepatocyte growth factor-regulated tyrosine kinase substrate), we purified this protein from B16-F1 mouse melanoma cells by anti-phosphotyrosine immunoaffinity chromatography and determined its partial amino acid sequences. On the basis of the amino acid sequences, we molecularly cloned the cDNA for mouse Hrs. The nucleotide sequence of the cDNA revealed that Hrs is a novel 775-amino-acid protein with a putative zinc finger domain that is structurally conserved in several other proteins. This protein also contained a proline-rich region and a proline- and glutamine-rich region. The expression of Hrs mRNA was detected in all adult mouse tissues tested and also in embryos. To analyze the Hrs cDNA product, we prepared a polyclonal antibody against bacterially expressed Hrs. Using this antibody, we showed by subcellular fractionation that Hrs is localized to the cytoplasm; we also showed that that tyrosine phosphorylation of Hrs is induced in cells treated with epidermal growth factor or platelet-derived growth factor. These results suggest that Hrs plays a unique and important role in the signaling pathway of growth factors.

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Isolation of an Entamoeba histolytica cDNA clone encoding a protein with a putative zinc finger domain

Molecular and Biochemical Parasitology ◽

10.1016/0166-6851(92)90256-j ◽

1992 ◽

Vol 50 (1) ◽

pp. 185-187 ◽

Cited By ~ 3

Author(s):

Samuel L. Stanley ◽

Ellen Li

Keyword(s):

Zinc Finger ◽

Entamoeba Histolytica ◽

Cdna Clone ◽

Zinc Finger Domain ◽

Putative Zinc Finger

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Activity of MCPIP1 RNase in tumor associated processes

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-019-1430-6 ◽

2019 ◽

Vol 38 (1) ◽

Cited By ~ 4

Author(s):

Katarzyna Miekus ◽

Jerzy Kotlinowski ◽

Agata Lichawska-Cieslar ◽

Janusz Rys ◽

Jolanta Jura

Keyword(s):

Zinc Finger ◽

Current Knowledge ◽

Negative Regulator ◽

Zinc Finger Domain ◽

Common Features ◽

Monocyte Chemoattractant ◽

Monocyte Chemoattractant Protein ◽

Terminal Domain ◽

The Common

Abstract The monocyte chemoattractant protein-induced protein (MCPIP) family consists of 4 members (MCPIP1–4) encoded by the ZC3h12A-D genes, which are located at different loci. The common features of MCPIP proteins are the zinc finger domain, consisting of three cysteines and one histidine (CCCH), and the N-terminal domain of the PilT protein (PilT-N-terminal domain (PIN domain)). All family members act as endonucleases controlling the half-life of mRNA and microRNA (miRNA). The best-studied member of this family is MCPIP1 (also known as Regnase-1). In this review, we discuss the current knowledge on the role of MCPIP1 in cancer-related processes. Because the characteristics of MCPIP1 as a fundamental negative regulator of immune processes have been comprehensively described in numerous studies, we focus on the function of MCPIP1 in modulating apoptosis, angiogenesis and metastasis.

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H2A.Z Functions To Regulate Progression through the Cell Cycle

Molecular and Cellular Biology ◽

10.1128/mcb.26.2.489-501.2006 ◽

2006 ◽

Vol 26 (2) ◽

pp. 489-501 ◽

Cited By ~ 60

Author(s):

Namrita Dhillon ◽

Masaya Oki ◽

Shawn J. Szyjka ◽

Oscar M. Aparicio ◽

Rohinton T. Kamakaka

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Chromosome Segregation ◽

Cell Cycle Progression ◽

S Phase ◽

Histone H2a ◽

Cycle Progression ◽

Checkpoint Pathway ◽

Cyclin Genes

ABSTRACT Histone H2A variants are highly conserved proteins found ubiquitously in nature and thought to perform specialized functions in the cell. Studies in yeast on the histone H2A variant H2A.Z have shown a role for this protein in transcription as well as chromosome segregation. Our studies have focused on understanding the role of H2A.Z during cell cycle progression. We found that htz1Δ cells were delayed in DNA replication and progression through the cell cycle. Furthermore, cells lacking H2A.Z required the S-phase checkpoint pathway for survival. We also found that H2A.Z localized to the promoters of cyclin genes, and cells lacking H2A.Z were delayed in the induction of these cyclin genes. Several different models are proposed to explain these observations.

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A conserved role of the duplicated Masculinizer gene in sex determination of the Mediterranean flour moth, Ephestia kuehniella

PLoS Genetics ◽

10.1371/journal.pgen.1009420 ◽

2021 ◽

Vol 17 (8) ◽

pp. e1009420

Author(s):

Sander Visser ◽

Anna Voleníková ◽

Petr Nguyen ◽

Eveline C. Verhulst ◽

František Marec

Keyword(s):

Sex Determination ◽

Zinc Finger ◽

Molecular Mechanisms ◽

Ephestia Kuehniella ◽

Close Relative ◽

Z Chromosome ◽

Zinc Finger Domain ◽

The Mediterranean ◽

Mediterranean Flour Moth

Sex determination in the silkworm, Bombyx mori, is based on Feminizer (Fem), a W-linked Fem piRNA that triggers female development in WZ individuals, and the Z-linked Masculinizer (Masc), which initiates male development and dosage compensation in ZZ individuals. While Fem piRNA is missing in a close relative of B. mori, Masc determines sex in several representatives of distant lepidopteran lineages. We studied the molecular mechanisms of sex determination in the Mediterranean flour moth, Ephestia kuehniella (Pyralidae). We identified an E. kuehniella Masc ortholog, EkMasc, and its paralog resulting from a recent duplication, EkMascB. Both genes are located on the Z chromosome and encode a similar Masc protein that contains two conserved domains but has lost the conserved double zinc finger domain. We developed PCR-based genetic sexing and demonstrated a peak in the expression of EkMasc and EkMascB genes only in early male embryos. Simultaneous knock-down experiments of both EkMasc and EkMascB using RNAi during early embryogenesis led to a shift from male- to female-specific splicing of the E. kuehniella doublesex gene (Ekdsx), their downstream effector, in ZZ embryos and resulted in a strong female-biased sex-ratio. Our results thus confirmed the conserved role of EkMasc and/or EkMascB in masculinization. We suggest that the C-terminal proline-rich domain, we have identified in all functionally confirmed Masc proteins, in conjunction with the masculinizing domain, is important for transcriptional regulation of sex determination in Lepidoptera. The function of the Masc double zinc finger domain is still unknown, but appears to have been lost in E. kuehniella.

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