ANALYSIS OF THE OCCURRENCE OF CIS-REGULATORY ESSENTIALS IN THE FIRST INTRONS OF HUMAN GENES

Author (s) : N. Roopa & K. Kalavathi

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Abstract :
Gene expression is primarily regulated through the interaction between transcription factors and their cognate cis-regulatory elements found in the promoter region of a gene. However, research studies have revealed, that the first introns of certain human genes also play a substantial role during the gene expression. A recent study has shown that the majority of the first introns of human housekeeping and tissue specific genes harbor cis-regulatory elements, like CAAT, GC and TATA boxes. The objectives of this study are to investigate the occurrence of such elements in the first introns of human housekeeping and tissue specific genes and to evaluate the first intron sequence similarity between human and closely related species. Appropriate first intron sequences were extracted from the ensembl genome browser. The knuth morris pratt algorithm written in perl, was executed to obtain motif counts. Expected motif counts for a given sequence were calculated using perl scripts. Results show, the motif counts do not directly proportionate to first intron length. Moreover, the average CAAT box count is higher in first introns of tissue specific genes and more than 95% of first intron sequence conservation was observed between human and closely related species which is a novel finding. Conclusively, this study speculates that the occurrences of motifs are unlikely to occur by chance along the first introns and there may be a correlation between the higher CAAT box counts and tissue specificity. Moreover, first intron sequences between human and closely related species are very highly conserved during evolution.

Keywords : Gene expression, human genes, first introns, cis-regulatory elements

Conference Date : 30/08/2019

Pages : 267

Paper ID : 19258