Here , we present genome-scale computational analyses indicating that ~76% of human core promoters lack TATA-like elements, have a high GC content, and are enriched in Sp1 binding sites (cfr GC box). We further identify two motifs - M3 (SCGGAAGY) and M22 (TGCGCANK) - that occur preferentially in human TATA-less core promoters. About 24% of human genes have a TATA-like element and their promoters are generally AT-rich; however, only ~10% of these TATA-containing promoters have the canonical TATA box (TATAWAWR). In contrast, ~46% of human core promoters contain the consensus INR (YYANWYY) and ~30% are INR-containing TATA-less genes. Significantly, ~46% of human promoters lack both TATA-like and consensus INR elements. Surprisingly, mammalian-type INR sequences are present - and tend to cluster - in the transcription start site (TSS) region of ~40% of yeast core promoters and the frequency of specific core promoter types appears to be conserved in yeast and human genomes. Gene Ontology analyses reveal that TATA-less genes in humans, as in yeast, are frequently involved in basic “housekeeping” processes, while TATA-containing genes are more often highly regulated, such as by biotic or stress stimuli.
[Articolo] Contenuto GC/AT nei promotori umani
1. Chuhu Yang, Eugene Bolotin, Tao Jiang, Frances M. Sladek and Ernest Martinez. Prevalence of the Initiator over the TATA box in human and yeast genes and identification of DNA motifs enriched in human TATA-less core promoters (PubMedCentral, 2007)
page revision: 5, last edited: 14 May 2013 15:04