The long term goals of this project are to isolate, characterize and study the expression of the human actin genes in both normal and pathological muscle and in cell differentiation. Utilizing the information obtained from these studies, we intend to design experiments which will help provide an understanding of how mammals in general, and humans in particular, use the actin multigene family to produce the various cellular structures which result from actin gene expression. We plan to isolate all the actin genes in the human genome. In addition to the cardiac-, skeletal- and cytoskeletal beta-actin gene already isolated, we will identify the cytoskeletal gamma- and two smooth muscle-actin genes. We will determine if the human genome encodes more than six different actin isotypes. The functional actin genes will be characterized in terms of the organization of coding and non-coding regions, the nucleotide sequence of putative RNA polymerase promoter sites at the 5' end of the genes and their chromosomal location. The regulation of actin gene expression will be evaluated to determine (1) how many actin genes are utilized to produce the cytoskeletal actins, (2) how many actin genes are regulated during human myogenesis in cell culture and (3) if transcription of the actin gene family is modulated in response to neoplastic transformation. We will define the regions of the human cardiac- and skeletal-actin genes which are responsible for their regulation during myogenesis. The human cardiac actin gene will be introduced into non-muscle cells and the ability of these cells to discriminate between a sarcomeric actin and endogenous non-muscle actin will be evaluated. We will explore the possibility of repressing the synthesis of specific actins by inducing expression of isotype specific anti-sense sequences.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD017031-09
Application #
3314143
Study Section
Molecular Biology Study Section (MBY)
Project Start
1982-07-01
Project End
1992-06-30
Budget Start
1989-07-01
Budget End
1992-06-30
Support Year
9
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Southern California
Department
Type
Schools of Medicine
DUNS #
041544081
City
Los Angeles
State
CA
Country
United States
Zip Code
90033
Ng, S Y; Erba, H; Latter, G et al. (1988) Modulation of microfilament protein composition by transfected cytoskeletal actin genes. Mol Cell Biol 8:1790-4
Erba, H P; Eddy, R; Shows, T et al. (1988) Structure, chromosome location, and expression of the human gamma-actin gene: differential evolution, location, and expression of the cytoskeletal beta- and gamma-actin genes. Mol Cell Biol 8:1775-89
Leavitt, J; Ng, S Y; Varma, M et al. (1987) Expression of transfected mutant beta-actin genes: transitions toward the stable tumorigenic state. Mol Cell Biol 7:2467-76
Leavitt, J; Ng, S Y; Aebi, U et al. (1987) Expression of transfected mutant beta-actin genes: alterations of cell morphology and evidence for autoregulation in actin pools. Mol Cell Biol 7:2457-66
Hickey, R; Skoultchi, A; Gunning, P et al. (1986) Regulation of a human cardiac actin gene introduced into rat L6 myoblasts suggests a defect in their myogenic program. Mol Cell Biol 6:3287-90
Wade, R; Gunning, P; Eddy, R et al. (1986) Nucleotide sequence, tissue-specific expression, and chromosome location of human carbonic anhydrase III: the human CAIII gene is located on the same chromosome as the closely linked CAI and CAII genes. Proc Natl Acad Sci U S A 83:9571-5
Lin, C S; Ng, S Y; Gunning, P et al. (1985) Identification and order of sequential mutations in beta-actin genes isolated from increasingly tumorigenic human fibroblast strains. Proc Natl Acad Sci U S A 82:6995-9
Garrison, J C; Hardeman, E; Wade, R et al. (1985) Isolation of full-length cDNAs encoding abundant adult human skeletal muscle mRNAs. Gene 38:177-88
Ng, S Y; Gunning, P; Eddy, R et al. (1985) Evolution of the functional human beta-actin gene and its multi-pseudogene family: conservation of noncoding regions and chromosomal dispersion of pseudogenes. Mol Cell Biol 5:2720-32
Leavitt, J; Gunning, P; Kedes, L et al. (1985) Smooth muscle alpha-action is a transformation-sensitive marker for mouse NIH 3T3 and Rat-2 cells. Nature 316:840-2