Structural and Functional Analysis of the Growth Arrest-Specific 11 (GAS11) Gene in Mouse Skeletal Muscle

Kari M. Morrissey
University of California, Los Angeles

Growth Arrest-Specific 11 (GAS11) is a novel cytoskeletal-associated protein that is upregulated in growth arrested cells. Previous Northern Blot Analysis of multiple human tissues reveals the ubiquitous expression of two transcripts of 1.8kb and 3.4kb. A transcript of 7.3kb was found to be expressed in skeletal and cardiac muscle, and a unique 1.4kb transcript was identified specifically in skeletal muscle (Whitmore et. al., 1998). However, these transcripts and the splicing pattern of the gene that encodes them have not yet been characterized. We have used Northern Blot analysis to delineate the splicing patterns of the GAS11 gene. Our data suggests the presence of five GAS11 transcripts (6.2kb, 4.14kb, 2.44kb, 1.54kb, and 0.96kb) present in mouse skeletal muscle in comparison to the four transcripts seen in human skeletal muscle. In addition, preliminary data shows the presence of exons 3 and 4 in the 6.2kb, 4.14kb, 2.44kb, and 0.96kb transcripts and their absence in the 1.54kb transcript. To isolate all of these transcripts from mouse skeletal muscle, Reverse Transcriptase Polymerase Chain Reaction has been used. To date we have isolated several candidate GAS11 transcripts. However, sequence analysis is needed to confirm their identity. The characterization of GAS11 at the transcriptional level can help us to decipher the molecular functions of the GAS11 protein in muscle development and movement.