Sandbox Reserved 818: Difference between revisions
From Proteopedia
Jump to navigationJump to search
Lea Clusan (talk | contribs) |
Lea Clusan (talk | contribs) |
||
| Line 85: | Line 85: | ||
This subunit catalyzes [http://en.wikipedia.org/wiki/ADP_ribosylation '''ADP-ribosylation'''] of the ''α-subunit of trimeric G proteins'', which disturbs functions of the target cells and therefore lead to various biological effects. | This subunit catalyzes [http://en.wikipedia.org/wiki/ADP_ribosylation '''ADP-ribosylation'''] of the ''α-subunit of trimeric G proteins'', which disturbs functions of the target cells and therefore lead to various biological effects. | ||
In facts, substrates of PTX are regulators of the membrane-bound adenylate cyclase. These G proteins bind GTP in order to transduce signals in the cell. When ADP-ribosylation by PTX occurs, ''the downregulation of the adenylate cyclase activity is inhibited''. This inhibition leads to increase cAMP levels in cells, which explains the amount of biological activities of the toxin. | In facts, substrates of PTX are regulators of the membrane-bound [http://en.wikipedia.org/wiki/Adenylate_cyclase adenylate cyclase]. These G proteins bind GTP in order to transduce signals in the cell. When ADP-ribosylation by PTX occurs, ''the downregulation of the adenylate cyclase activity is inhibited''. This inhibition leads to increase [http://en.wikipedia.org/wiki/Cyclic_adenosine_monophosphate cAMP] levels in cells, which explains the amount of biological activities of the toxin. | ||
The ADP-ribosylation of trimeric G proteins occurs on a '''cysteine residue''' in the ''C-terminal part of the α-subunit'' | The ADP-ribosylation of trimeric G proteins occurs on a '''cysteine residue''' in the ''C-terminal part of the α-subunit'' | ||
