A Human Homologue of theSchizosaccharomyces pombe rad1+Checkpoint Gene Encodes an Exonuclease

Abstract trithorax (trx) encodes chromosome-binding proteins required throughout embryogenesis and imaginal development for tissue- and cell-specific levels of transcription of many genes including homeotic genes of the ANT-C and BX-C. trx encodes two protein isoforms that contain conserved motifs including a C-terminal SET domain, central PHD fingers, an N-terminal DNA-binding homology, and two short motifs also found in the TRX human homologue, ALL1. As a first step to characterizing specific developmental functions of TRX, I examined phenotypes of 420 combinations of 21 trx alleles. Among these are 8 hypomorphic alleles that are sufficient for embryogenesis but provide different levels of trx function at homeotic genes in imaginal cells. One allele alters the N terminus of TRX, which severely impairs larval and imaginal growth. Hypomorphic alleles that alter different regions of TRX equivalently reduce function at affected genes, suggesting TRX interacts with common factors at different target genes. All hypomorphic alleles examined complement one another, suggesting cooperative TRX function at target genes. Comparative effects of hypomorphic genotypes support previous findings that TRX has tissue-specific interactions with other factors at each target gene. Some hypomorphic genotypes also produce phenotypes that suggest TRX may be a component of signal transduction pathways that provide tissue- and cell-specific levels of target gene transcription.

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Characterization of HRG22, a Human Homologue of the Putative Tumor Suppressor Gene HIC1

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.2001.5624 ◽

2001 ◽

Vol 287 (2) ◽

pp. 427-434 ◽

Cited By ~ 19

Author(s):

Sophie Deltour ◽

Sébastien Pinte ◽

Cateline Guérardel ◽

Dominique Leprince

Keyword(s):

Tumor Suppressor ◽

Tumor Suppressor Gene ◽

Suppressor Gene ◽

Human Homologue ◽

Putative Tumor Suppressor Gene ◽

Putative Tumor Suppressor

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Pituitary Tumor-transforming Gene Protein Associates with Ribosomal Protein S10 and a Novel Human Homologue of DnaJ in Testicular Cells

Journal of Biological Chemistry ◽

10.1074/jbc.274.5.3151 ◽

1999 ◽

Vol 274 (5) ◽

pp. 3151-3158 ◽

Cited By ~ 29

Author(s):

Lin Pei

Keyword(s):

Ribosomal Protein ◽

Pituitary Tumor ◽

Human Homologue ◽

Pituitary Tumor Transforming Gene ◽

Testicular Cells ◽

Transforming Gene

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Cloning and characterization of RECQL, a potential human homologue of the Escherichia coli DNA helicase RecQ.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)43957-9 ◽

1994 ◽

Vol 269 (47) ◽

pp. 29838-29845

Author(s):

K L Puranam ◽

P J Blackshear

Keyword(s):

Escherichia Coli ◽

Dna Helicase ◽

Human Homologue

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Specification of Actin Filament Function and Molecular Composition by Tropomyosin Isoforms

Molecular Biology of the Cell ◽

10.1091/mbc.e02-04-0244 ◽

2003 ◽

Vol 14 (3) ◽

pp. 1002-1016 ◽

Cited By ~ 180

Author(s):

Nicole S. Bryce ◽

Galina Schevzov ◽

Vicki Ferguson ◽

Justin M. Percival ◽

Jim J.-C. Lin ◽

...

Keyword(s):

Cell Size ◽

Functional Properties ◽

Actin Filament ◽

Actin Filaments ◽

Myosin Ii ◽

Molecular Composition ◽

Cellular Migration ◽

Stress Fibers ◽

Human Homologue ◽

Tropomyosin Isoforms

The specific functions of greater than 40 vertebrate nonmuscle tropomyosins (Tms) are poorly understood. In this article we have tested the ability of two Tm isoforms, TmBr3 and the human homologue of Tm5 (hTM5NM1), to regulate actin filament function. We found that these Tms can differentially alter actin filament organization, cell size, and shape. hTm5NM1was able to recruit myosin II into stress fibers, which resulted in decreased lamellipodia and cellular migration. In contrast, TmBr3 transfection induced lamellipodial formation, increased cellular migration, and reduced stress fibers. Based on coimmunoprecipitation and colocalization studies, TmBr3 appeared to be associated with actin-depolymerizing factor/cofilin (ADF)-bound actin filaments. Additionally, the Tms can specifically regulate the incorporation of other Tms into actin filaments, suggesting that selective dimerization may also be involved in the control of actin filament organization. We conclude that Tm isoforms can be used to specify the functional properties and molecular composition of actin filaments and that spatial segregation of isoforms may lead to localized specialization of actin filament function.

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Characterization of a human homologue of the murine peripheral lymph node homing receptor.

The Journal of Cell Biology ◽

10.1083/jcb.109.1.421 ◽

1989 ◽

Vol 109 (1) ◽

pp. 421-427 ◽

Cited By ~ 60

Author(s):

B R Bowen ◽

T Nguyen ◽

L A Lasky

Keyword(s):

Cell Adhesion ◽

Lymph Node ◽

Adhesion Molecule ◽

Carbohydrate Binding ◽

Human Homologue ◽

Peripheral Lymph Node ◽

Homing Receptor ◽

Lymph Node Homing ◽

Peripheral Lymph ◽

Human Receptor

Lymphocyte trafficking is a fundamental aspect of the immune system that allows B and T lymphocytes with diverse antigen recognition specificities to be exposed to various antigenic stimuli in spatially distinct regions of an organism. A lymphocyte adhesion molecule that is involved with this trafficking phenomenon has been termed the homing receptor. Previous work (Lasky, L., T. Yednock, M. Singer, D. Dowbenko, C. Fennie, H. Rodriguez, T. Nguyen, S. Stachel, and S. Rosen. 1989. Cell. 56:1045-1055) has characterized a cDNA clone encoding a murine homing receptor that is involved in trafficking of lymphocytes to peripheral lymph nodes. This molecule was found to contain a number of protein motifs, the most intriguing of which was a carbohydrate binding domain, or lectin, that is apparently involved in the adhesive interaction between murine lymphocytes and peripheral lymph node endothelium. In this study, we have used the murine cDNA clone to isolate a human homologue of this peripheral lymph node-specific adhesion molecule. The human receptor was found to be highly homologous to the murine receptor in overall sequence, but showed no sequence similarity to another surface protein that may be involved with human lymphocyte homing, the Hermes glycoprotein. The extracellular region of the human receptor contained an NH2 terminally located carbohydrate binding domain followed by an EGF-like domain and a domain containing two repeats of a complement binding motif. Transient cell transfection assays using the human receptor cDNA showed that it encoded a surface glycoprotein that cross reacted with a polyclonal antibody directed against the murine peripheral lymph node homing receptor. Interestingly, the human receptor showed a high degree of sequence homology to another human cell adhesion glycoprotein, the endothelial cell adhesion molecule ELAM.

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