Unknown,Transcriptomics,Genomics,Proteomics

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Differential gene expression in heart tubes of hand[173] null mutants vs. w[1118]

ABSTRACT: Hand proteins belong to the highly conserved family of basic Helix-Loop-Helix transcription factors and are critical for distinct developmental processes, including cardiogenesis and neurogenesis in vertebrates. In Drosophila melanogaster a single orthologous hand gene is expressed with absence of the respective protein causing semilethality during early larval instars. Surviving adult animals suffer from shortened lifespan associated with a disorganized myofibrillar structure being apparent in the dorsal vessel, the wing hearts and in midgut tissue. Based on these data, the major biological significance of Hand seems to be related to muscle development, maintenance or function; however, up to now the physiological basis for Hand functionality remained elusive. Thus, the identification of genes whose expression is, directly or indirectly, regulated by Hand has considerable relevance with respect to understanding its biological functionality in flies and vertebrates. Beneficially, hand mutants are viable and exhibit affected tissues which renders Drosophila an ideal model to investigate up- or downregulated target genes by a comparative microarray approach focusing on the respective tissues from mutant specimens. Our present work reveals for the first time that Drosophila melanogaster Hand regulates the expression of numerous genes of diverse physiological relevancy including distinct factors required for proper muscle development and function, such as Zasp52 or Msp-300. These results relate Hand activity to muscle integrity and functionality and may thus be highly beneficial in order to understand hand phenotypes described earlier. For hand[173] null mutants and w[1118] heart tissues of wandering 3d instar larvae were dissected, RNA was isolated and samples were subjected to microarray analysis.

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Julia Hoffmann

PROVIDER: E-GEOD-64429 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Differential gene expression in heart tubes of hand[173] null mutants vs. w[1118]

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