Disease relevance of Actg1

• Parent B16 melanoma and B16-F1 cell lines express a third actin (Ax) in addition to beta- and gamma-actin [1].
• In contrast, transfectants expressing the gamma-actin gene deleted for intron III (gamma 156) were rounded with blebs over the cell surface and showed decreased surface area [2].
• The subsequent insertion of an endogenous retrovirus interrupted the gamma-actin pseudogene within its 3'-untranslated region [3].
• We have cloned a processed gene related to cytoplasmic gamma-actin from a phage library of mouse brain DNA [4].
• Differential requirements of gag and gamma-actin domains for transforming potential of Gardner-Rasheed feline sarcoma virus [5].

High impact information on Actg1

• Subcellular sorting of isoactins: selective association of gamma actin with skeletal muscle mitochondria [6].
• Accompanying this morphological change are large and specific decreases in biosynthetic rates for beta and gamma actin, vimentin and alpha and beta tubulin, as detected by one- and two-dimensional gel electrophoresis [7].
• All human fibroblast strains, normal and transformed, synthesize two electrophoretic forms of actin (beta- and gamma-actin) [8].
• The human salivary amylase genes are associated with two inserted elements, a gamma-actin-processed pseudogene and an endogenous retroviral-like element [9].
• Our data demonstrate that the dystrophin complex forms a mechanically strong link between the sarcolemma and the costameric cytoskeleton through interaction with gamma-actin filaments [10].

Chemical compound and disease context of Actg1

• Human neuroblastoma SH-EP cells transfected with gamma-actin siRNA displayed higher relative resistance to paclitaxel (P<.001), vinblastine (P = .04), and epothilone B (P = .045) than mock-transfected cells [11].

Biological context of Actg1

• The 2.1-kb actin mRNA codes for cytoplasmic beta- and gamma-actin and is found throughout spermatogenesis, while the 1.5-kb actin mRNA is first detected in postmeiotic cells [12].
• In the present study, we show that the response of beta- and gamma-actin genes is due to the synthesis of a protein(s) acting at a 5' regulatory element that may be independent of or require sequences in addition to the serum response element (SRE) [13].
• We conclude that the relative gene expression of beta- and gamma-actin is of relevance to the control of myoblast cytoarchitecture [14].
• The impact of the human beta- and gamma-actin genes on myoblast cytoarchitecture was examined by their stable transfection into mouse C2 myoblasts [14].
• Mouse cytoskeletal gamma-actin: analysis and implications of the structure of cloned cDNA and processed pseudogenes [15].

Anatomical context of Actg1

• Testicular SMGA mRNA was first detected and increased substantially in amount during spermiogenesis in the germ cells, in contrast to the decrease of the cytoplasmic beta- and gamma-actin mRNAs towards the end of spermatogenesis [12].
• High level expression of transfected beta- and gamma-actin genes differentially impacts on myoblast cytoarchitecture [14].
• High level expression of the mutant beta-actin produced decreases in cell surface area and disruption of the actin microfilament network similar to that seen with transfection of the gamma-actin gene [14].
• A novel role for non-muscle gamma-actin in skeletal muscle sarcomere assembly [16].
• Consequently, a modified model is proposed which describes the role of gamma-actin in skeletal sarcomere assembly [16].

Associations of Actg1 with chemical compounds

• In contrast, C2 clones with high levels of human gamma-actin expression showed decreases in cell surface area [14].
• Immediately after transfection with E51 cDNA, both alpha-aminoisobutyric acid (AIB) and proline uptake in the mutated yeast were increased, particularly at pH 5 [17].
• An inhibitor of protein synthesis, cycloheximide, was also found to induce beta- and gamma-actin mRNA accumulation [18].
• The level of gamma-actin mRNA was elevated in resting cells by 12-O-tetradecanoylphorbol-13-acetate, calcium ionophore A23187, and bombesin and to a lesser extent by cholera toxin, fibroblast-derived growth factor, and dibutyryl cyclic AMP [19].
• However, insulin, vasopressin, or epidermal growth factor failed to enhance gamma-actin mRNA levels in resting cells [19].

Regulatory relationships of Actg1

• Upon differentiation, neuroblastoma cells reorganize their actin cytoskeleton and gamma actin is induced to polymerize whereas beta actin polymers are partially disassembled [20].

Other interactions of Actg1

• In the case of the beta sm and gamma-actin transfectants, a two-fold decrease in the cell surface area was coupled, as predicted, with a decrease in vinculin and talin expression [21].
• Localisation of gamma-actin in a different area of the myotube to the muscle-specific sarcomeric alpha-actin also indicated a distinct role for gamma-actin [16].
• Organisation of non-muscle gamma-actin and co-localisation with sarcomeric alpha-actinin, an early marker of sarcomere assembly and a major component of Z lines, was noted. gamma-Actin was also identified in young myotubes with developing sarcomeric myofibrils in regenerating adult mouse muscle [16].
• The damage to gamma-actin and DNA polymerase-beta genes was detected within 20 min of reperfusion based on the presence of formamidopyrimidine DNA N-glycosylase-sensitive sites [22].
• Poly-ADP-ribosylated peptides identified using a proteomics approach yielded several proteins potentially associated with memory, including structural proteins (tubulin alpha and beta, gamma-actin, and alpha-internexin neuronal intermediate filament protein) and 14-3-3gamma [23].

Analytical, diagnostic and therapeutic context of Actg1

• Using fluorescent double in situ hybridization we describe the simultaneous intracellular localization of both beta and gamma actin mRNA [24].
• The Actg gene was mapped to mouse chromosome 6 by Southern blot analysis of DNA isolated from 15 mouse-hamster hybrid cell lines [25].
• The major cytoskeletal protein, gamma-actin, was down-regulated in the VCR-resistant leukemia xenografts; in contrast, there was no significant change in beta-actin expression [26].
• A partial sequence analysis of the pME1 insert DNA indicated that it contained a 104-base-pair stretch with extensive homology to the 3' untranslated region of gamma actin [19].
• DNA from ten mouse genomic clones, each containing distinct gamma-actin processed pseudogenes, was subjected to electron microscopic heteroduplex analysis, and in three cases (lambda mA36, lambda mA118 and lambda mA119) the heteroduplex formed with the DNA of a reference clone was found to be interrupted by a single-stranded loop [27].

References