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Group:MUZIC:DARP
From Proteopedia
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| 1n0r, resolution 1.50Å () | |||||||||
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| Related: | 1n0q | ||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Introduction
Diabetes related ankyrin repeat protein DARP (Ankrd23) and its two close homologs Ankrd2/Arpp and Ankrd1/CARP correspond to a conserved gene family of muscle ankyrin repeat proteins (MARPs). [1] DARP is expressed in both heart and skeletal muscle (in addition to brown fat) and was identified by its upregulation in Type 2 diabetes and insulin-resistant animals, suggesting a potential role in energy metabolism. [2]
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Structure
DARP contains putative nuclear localization signals,four tandem ankyrin-like repeats, potential coiled-coil dimerization motif within its unique aminoterminal domain that mediates the formation of homodimers. [3]The amino acid sequence of DARP showed high similarity to cardiac ankyrin-repeat protein (CARP) and ankyrin-repeat domain 2 (Ankrd2) with 45 and 36% identities, respectively
Gene Function
DARP knock out muscle fibers were less stiff, tended to have longer resting sarcomere lengths, and expressed a longer isoform of titin than their wild-type counterparts, indicating that this protein may play a role in the passive mechanical behavior of muscle. [4] DARP expression is altered by a change of energy supply and energy metabolic condition, induced by excess fatty acid treatment in vitro and fasting in vivo. [2] The expression of DARP is induced during recovery following starvation.
Interaction
DARP interacts with a tyrosine-rich binding motif between Ig80 and Ig81 of titin and with myopalladin. [1]
Refrences
- ↑ 1.0 1.1 Miller MK, Bang ML, Witt CC, Labeit D, Trombitas C, Watanabe K, Granzier H, McElhinny AS, Gregorio CC, Labeit S. The muscle ankyrin repeat proteins: CARP, ankrd2/Arpp and DARP as a family of titin filament-based stress response molecules. J Mol Biol. 2003 Nov 7;333(5):951-64. PMID:14583192
- ↑ 2.0 2.1 Ikeda K, Emoto N, Matsuo M, Yokoyama M. Molecular identification and characterization of a novel nuclear protein whose expression is up-regulated in insulin-resistant animals. J Biol Chem. 2003 Feb 7;278(6):3514-20. Epub 2002 Nov 26. PMID:12456686 doi:10.1074/jbc.M204563200
- ↑ Witt SH, Labeit D, Granzier H, Labeit S, Witt CC. Dimerization of the cardiac ankyrin protein CARP: implications for MARP titin-based signaling. J Muscle Res Cell Motil. 2005;26(6-8):401-8. PMID:16450059 doi:10.1007/s10974-005-9022-9
- ↑ Barash IA, Bang ML, Mathew L, Greaser ML, Chen J, Lieber RL. Structural and regulatory roles of muscle ankyrin repeat protein family in skeletal muscle. Am J Physiol Cell Physiol. 2007 Jul;293(1):C218-27. Epub 2007 Mar 28. PMID:17392382 doi:10.1152/ajpcell.00055.2007
