Angiotensin converting enzyme (ACE1) is a key regulatory enzyme in the pathway t
ID: 149739 • Letter: A
Question
Angiotensin converting enzyme (ACE1) is a key regulatory enzyme in the pathway that regulates bloodpressur. ACe1 activation leads to the contrsiticiton of blood vessels and the retention of salt and water. In comparing normal to hypersentive rats, it was determined that there was diference in the histone modifications H3Ac, H3K4, and H3K9 in aorta, heart, kidney, and liver. For each modificaiton, is it associated with increased or decreased expression of ACE1, and which rat type would you expect to be enriched for the modification (normal or hypersensitive)? Explain.
Modification Rat with Enrichment for this Modification ACE1 Expression in Rat with Modification H3Ac H3K4 (me3) H3K9 (me2)Explanation / Answer
ACE1 is a crucial regulator of Blood pressure , it facilitates production of Angiotensin II from Angiotensin I which is an inactive form.
Disruption of ACE1 expression leads to reduction in Angiotension II in blood which helps in reduction of blood pressure.
ACE1 is highly expressed in lungs and kidneys
ACE1 transcription is quite low in liver
In Normal mice, in liver, the ACE 1 promoter should be enriched with the modification which serve as repressive mark such as H3K9(me2).Whereas in Lung, Kidneys it should be enriched with Activating marks such as H3Ac and H3K4(me2).
Modification Normal Rat Hypersensitive Rat
H3Ac active mark-- more H3ac Increased ACE1 activation
H3K4 (me3) active mark----- more H3K4(me3)
H3K9 (me2)-- repressive mark enriched in hypersensitive rats