1qxp

<table><tr><td colspan='2'>[[1qxp]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Buffalo_rat Buffalo rat]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QXP OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1QXP FirstGlance]. <br>

</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1df0|1df0]], [[1dkv|1dkv]]</div></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Calpain-1 Calpain-1], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.22.52 3.4.22.52] </span></td></tr>

[[https://www.uniprot.org/uniprot/CAN2_RAT CAN2_RAT]] Calcium-regulated non-lysosomal thiol-protease which catalyze limited proteolysis of substrates involved in cytoskeletal remodeling and signal transduction.

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== Publication Abstract from PubMed ==

The two Ca2+-dependent cysteine proteases, micro- and m-calpain, are involved in various Ca2+-linked signal pathways but differ markedly in their Ca2+ requirements for activation. We have determined the structure of a micro-like calpain, which has 85% micro-calpain sequence (the first 48 and the last 62 residues of the large subunit are those from m-calpain) and a low Ca2+ requirement. This construct was used because micro-calpain itself is too poorly expressed. The structure of micro-like calpain is very similar in overall fold to that of m-calpain as expected, but differs significantly in two aspects. In comparison with m-calpain, the catalytic triad residues in micro-like calpain, His and Cys, are much closer together in the absence of Ca2+, and significant portions of the Ca2+ binding EF-hand motifs are disordered and more flexible. These structural differences imply that Ca2+-free micro-calpain may represent a partially activated structure, requiring lower Ca2+ concentration to trigger its activation.

Crystal structure of a micro-like calpain reveals a partially activated conformation with low Ca2+ requirement.,Pal GP, De Veyra T, Elce JS, Jia Z Structure. 2003 Dec;11(12):1521-6. PMID:14656436<ref>PMID:14656436</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Buffalo rat]]

[[Category: Calpain-1]]

[[Category: Elce, J S]]

[[Category: Jia, Z]]

[[Category: Pal, G P]]

[[Category: Veyra, T D]]

[[Category: Catalytic triad]]

[[Category: Mu-calpain]]