E-GEOD-4711 - Transcription profiling of mouse polysome vs RNP fractions from testis obtained from prepuberttal and adult animals to investigate post transcriptional control mechanisms in gametes
Submitted on 24 April 2006, released on 23 November 2007, last updated on 27 March 2012
Gametes rely heavily on post-transcriptional control mechanisms to regulate their differentiation. In eggs, the storage and selective temporal activation of maternal mRNAs is essential for normal development. In the male, transcription ceases during spermiogenesis necessitating the post-transcriptional regulation of many paternal mRNAs required for spermatid differentiation and spermatozoan function. Messenger RNAs that are being actively translated form polysomes. whereas translationally inactive mRNAs are often sequestered in ribonucleoproteins (RNPs). Here we combine polysome display and microarray analyses of RNP and polysome fractions of testes from prepubertal and adult mice to characterize the translation state of individual mRNAs as spermatogenesis proceeds.. Consistent with published reports, many post-meiotic mRNAs known to be translationally delayed shift from the RNPs into the polysomes, confirming the validity of this approach. In addition, based upon the criterion of movement from RNPs to polysomes, we detect another 742 mouse testicular genes showing dramatic shifts between RNPs and polysomes. One sub-group of 35 genes including the known translationally delayed Pgk2, are initially transcribed and translationally repressed in meiotic spermatocytes, and translated post-meiotically. This high-through-put approach defines the changing translation patterns of a large number of genes as male germ cells differentiate and identifies a new group of post-transcriptionally regulated meiotic transcripts for future study. Mouse testes from animals of 3 different ages were fractionated on a sucrose gradient and transcripts were quantified in the RNP and Polysome fractions. Transcripts were identified that changed their RNP/Polysome representation at the different developmental time points.
transcription profiling by array, co-expression, development or differentiation
Norman B. Hecht
Expression profiling reveals meiotic male germ cell mRNAs that are translationally up- and down-regulated. Naoko Iguchi, John W Tobias, Norman B Hecht. Proc Natl Acad Sci U S A 103(20):7712-7 (2006)