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Showing posts with the label ACE2

Binding of SARS-CoV-2 to ACE2 does not affect ACE2 enzymatic function

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The Biochemical Society posted a recording of a fascinating webinar titled ACE2: Friend or Foe. I have indexed the third portion, a talk by Prof Michael Bader on the non-enzymatic functions of ACE2. I hope to index the other portions soon. Highlights:  - ACE2 enzymatic function is not affected by SARS-CoV-2 binding. Dr Roger Seheult, a pulmonologist, and others have proposed what I thought to be a quite plausible hypothesis that loss of ACE2 function due to SARS-CoV-2 binding results in high levels of oxidative stress which in turn causes hypercoagulability and attendant pathologies. Loss of ACE2 activity may be occurring due to reduced ACE2 transcription, however [ see previous post on this ]. - Vascular pericytes are potential targets of infection (very interesting, IMHO) - AT2 pneumocytes are targets of infection in lung tissue - loss of ACE2 results in reduced tryptophan uptake due to loss of amino acid transport function > reduction in serotonin production > loss of exercis

SARS-CoV-2 induced expression changes in ACE2 and associated genes

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[2020-07-07] Fadason et al. (2020)           A preprint  by Fadason et al. [1] discusses a mechanism by which SARS-CoV-2 could alter gene expression of ACE2 and associated genes and produce a host environment that favors its replication. In doing so, it looks like the virus not only 'takes out' ACE2 by binding with its catalytic domain (see update below), it may also decrease ACE2 expression. I am not familiar with this type of alteration of chromatin structure and I don't know how long lasting the changes could be. Some epigenetic alterations can be quite long lasting, even multi-generational.         S everal genes in the network that are also affected impact lipid metabolism and gluconeogenesis. Gluconeogenesis can also be a response to hypoxia [2] and is a common feature of the acute phase response in both infection and injury [5].                      The article does not discuss changes in collectrin expression. The collectrin and ACE2 genes are located on the X chro