ESSAY QUESTION Each of the cells in your body contains the same DNA sequence. Th
ID: 270180 • Letter: E
Question
ESSAY QUESTION Each of the cells in your body contains the same DNA sequence. This sequence includes the gene encoding Protein X (Gene X). However, the Protein X made in your intestinal epithelial cells is not identical to that made in your neurons A) Describe one way regulation of Gene X could differ quantitatively in these two cell types resulting in more expression of Gene X in one cell type compared with the other B) Describ products (i.e, different primary structures) in the two cell types Key terms: promoter, enhancer, transcription factors, splicing, signaling, editing e a second way that Gene X could be regulated to yield qualitatively differentExplanation / Answer
Ans A- Most probable regulatory mechanism for a gene to express at different rates in different cell types is by cell signalling.
A hormone that can regulate the rate of protein X is secreted by a gland in our body. This hormone then binds to its target cell and intiate cell signaling pathways that enhance the rate of mRNA formation by activating transcription factors. It generates a enhancer molecule that binds to the specific promoter sequence upstream to the gene X and enhances the synthesis of mRNA encoding for protein X.
Like this the overall rate of protein X synthesis is increased in the target cell.
Ans B- Gene X make qualitatively different products in the two cells by the method of alternative splicing and mRNA editing. mRNA of gene X is edited after synthesis. Alternative splicing of the mRNA is done and sequences that are acting as Exons in one cell are spliced as introns in other. Hence due to change in mRNA sequence the protein X product is also changed.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.