1tl9: Difference between revisions

From Proteopedia
Jump to navigationJump to search
OCA (talk | contribs)
New page: left|200px<br /><applet load="1tl9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1tl9, resolution 1.80Å" /> '''High resolution crys...
 
OCA (talk | contribs)
No edit summary
Line 1: Line 1:
[[Image:1tl9.jpg|left|200px]]<br /><applet load="1tl9" size="450" color="white" frame="true" align="right" spinBox="true"  
[[Image:1tl9.jpg|left|200px]]<br /><applet load="1tl9" size="350" color="white" frame="true" align="right" spinBox="true"  
caption="1tl9, resolution 1.80&Aring;" />
caption="1tl9, resolution 1.80&Aring;" />
'''High resolution crystal structure of calpain I protease core in complex with leupeptin'''<br />
'''High resolution crystal structure of calpain I protease core in complex with leupeptin'''<br />


==Overview==
==Overview==
The endogenous calpain inhibitor, calpastatin, modulates some, patho-physiological aspects of calpain signaling. Excess calpain can, escape this inhibition and as well, many calpain isoforms and, autolytically generated protease core fragments are not inhibited by, calpastatin. There is a need, therefore, to develop specific, cell-permeable calpain inhibitors to block uncontrolled proteolysis and, prevent tissue damage during brain and heart ischemia, spinal-cord injury, and Alzheimer's diseases. Here, we report the first high-resolution, crystal structures of rat mu-calpain protease core complexed with two, traditional, low molecular mass inhibitors, leupeptin and E64. These, structures show that access to a slightly deeper, but otherwise, papain-like active site is gated by two flexible loops. These loops are, divergent among the calpain isoforms giving a potential structural basis, for substrate/inhibitor selectivity over other papain-like cysteine, proteases and between members of the calpain family.
The endogenous calpain inhibitor, calpastatin, modulates some patho-physiological aspects of calpain signaling. Excess calpain can escape this inhibition and as well, many calpain isoforms and autolytically generated protease core fragments are not inhibited by calpastatin. There is a need, therefore, to develop specific, cell-permeable calpain inhibitors to block uncontrolled proteolysis and prevent tissue damage during brain and heart ischemia, spinal-cord injury and Alzheimer's diseases. Here, we report the first high-resolution crystal structures of rat mu-calpain protease core complexed with two traditional, low molecular mass inhibitors, leupeptin and E64. These structures show that access to a slightly deeper, but otherwise papain-like active site is gated by two flexible loops. These loops are divergent among the calpain isoforms giving a potential structural basis for substrate/inhibitor selectivity over other papain-like cysteine proteases and between members of the calpain family.


==About this Structure==
==About this Structure==
1TL9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with CA and ACE as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Calpain-1 Calpain-1], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.22.52 3.4.22.52] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1TL9 OCA].  
1TL9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=ACE:'>ACE</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Calpain-1 Calpain-1], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.22.52 3.4.22.52] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TL9 OCA].  


==Reference==
==Reference==
Line 14: Line 14:
[[Category: Rattus norvegicus]]
[[Category: Rattus norvegicus]]
[[Category: Single protein]]
[[Category: Single protein]]
[[Category: Campbell, R.L.]]
[[Category: Campbell, R L.]]
[[Category: Cuerrier, D.]]
[[Category: Cuerrier, D.]]
[[Category: Davies, P.L.]]
[[Category: Davies, P L.]]
[[Category: Moldoveanu, T.]]
[[Category: Moldoveanu, T.]]
[[Category: ACE]]
[[Category: ACE]]
Line 22: Line 22:
[[Category: covalently-linked inhibitor at the active site cysteine forms a hemithioacetal]]
[[Category: covalently-linked inhibitor at the active site cysteine forms a hemithioacetal]]


''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 03:22:19 2007''
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:14:50 2008''