alpha-crystallin domain (ACD) found in alpha-crystallin-type small heat shock proteins, and a similar domain found in p23 (a cochaperone for Hsp90) and in other p23-like proteins.; The alpha-crystallin-Hsps_p23-like superfamily includes the alpha-crystallin domain (ACD) of alpha-crystallin-type small heat shock proteins (sHsps) and a similar domain found in p23-like proteins. sHsps are small stress induced proteins with monomeric masses between 12-43 kDa, whose common feature is this ACD. sHsps are generally active as large oligomers consisting of multiple subunits, and are believed to be ATP-independent chaperones that prevent aggregation and are important in refolding in combination with other Hsps. p23 is a cochaperone of the Hsp90 chaperoning pathway. It binds Hsp90 and participates in the folding of a number of Hsp90 clients including the progesterone receptor. p23 also has a passive chaperoning activity. p23 in addition may act as the cytosolic prostaglandin E2 synthase. Included in this superfamily is the p23-like C-terminal CHORD-SGT1 (CS) domain of suppressor of G2 allele of Skp1 (Sgt1) and the p23-like domains of human butyrate-induced transcript 1 (hB-ind1), NUD (nuclear distribution) C, Melusin, and NAD(P)H cytochrome b5 (NCB5) oxidoreductase (OR).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06497     4 EVRSDRDKFTIYLDVKHFSPEDLTVKVLDDYVEIHGKHSERQDDHGYISREFHRRYRLPSNVDQSAITCSLSADGMLTFS 83

                  ...
gi 1392113100 106 GPK 108
Cdd:cd06497    84 GPK 86

Alpha-crystallin domain found in the small heat shock protein (sHsp) alphaA-crystallin (HspB4, 20kDa). sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. Alpha crystallin, an abundant protein in the mammalian lens, is a large (700 kDa) heteropolymer composed of HspB4 and HspB5, generally in a molar ratio of HspB4:HspB5 of 3:1. Only trace amounts of HspB4 are found in tissues other than the lens. HspB5 does not belong to this group. Mutations inHspB4 have been associated with Autosomal Dominant Congenital Cataract (ADCC). The chaperone-like functions of HspB4 are considered important for maintaining lens transparency and preventing cataract.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06497     4 EVRSDRDKFTIYLDVKHFSPEDLTVKVLDDYVEIHGKHSERQDDHGYISREFHRRYRLPSNVDQSAITCSLSADGMLTFS 83

                  ...
gi 1392113100 106 GPK 108
Cdd:cd06497    84 GPK 86

Small heat shock protein IbpA, HSP20 family [Posttranslational modification, protein turnover, chaperones];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1392113100  32 DKFVIFLDVKHFSPEDLTVKVQDDFVEIHG--KHNERQDDHGYISRE-----FHRRYRLPSNVDQSALSCSLSaDGMLT 103
Cdd:COG0071     9 DAYVITADLPGVDKEDIDVTVEGNVLTISGerKEEEEEEGENYLRRErrygsFERSFTLPDDVDVDKIEASYE-NGVLT 86

Alpha-crystallin domain found in the small heat shock protein (sHsp) alphaA-crystallin (HspB4, 20kDa). sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. Alpha crystallin, an abundant protein in the mammalian lens, is a large (700 kDa) heteropolymer composed of HspB4 and HspB5, generally in a molar ratio of HspB4:HspB5 of 3:1. Only trace amounts of HspB4 are found in tissues other than the lens. HspB5 does not belong to this group. Mutations inHspB4 have been associated with Autosomal Dominant Congenital Cataract (ADCC). The chaperone-like functions of HspB4 are considered important for maintaining lens transparency and preventing cataract.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06497     4 EVRSDRDKFTIYLDVKHFSPEDLTVKVLDDYVEIHGKHSERQDDHGYISREFHRRYRLPSNVDQSAITCSLSADGMLTFS 83

                  ...
gi 1392113100 106 GPK 108
Cdd:cd06497    84 GPK 86

Alpha-crystallin domain (ACD) of metazoan alpha-crystallin-type small(s) heat shock proteins (Hsps). sHsps are small stress induced proteins with monomeric masses between 12 -43 kDa, whose common feature is the Alpha-crystallin domain (ACD). sHsps are generally active as large oligomers consisting of multiple subunits, and are believed to be ATP-independent chaperones that prevent aggregation and are important in refolding in combination with other Hsps.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06526     1 VVNDDDEKFQVTLDVKGFKPEELKVKVSDNKLVVEGKHEEREDEHGYVSREFTRRYQLPEGVDPDSVTSSLSSDGVLTIE 80

                  ...
gi 1392113100 106 GPK 108
Cdd:cd06526    81 APK 83

Alpha crystallin domain (ACD) found in mammalian small (s)heat shock protein (Hsp)-27 (also denoted HspB1 in human) and similar proteins. sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. Hsp27 shows enhanced synthesis in response to stress. It is a molecular chaperone which interacts with a large number of different proteins. It is found in many types of human cells including breast, uterus, cervix, platelets and cancer cells. Hsp27 has diverse cellular functions including, chaperoning, regulation of actin polymerization, keratinocyte differentiation, regulation of inflammatory pathways in keratinocytes, and protection from oxidative stress through modulating glutathione levels. It is also a subunit of AUF1-containing protein complexes. It has been linked to several transduction pathways regulating cellular functions including differentiation, cell growth, development, and apoptosis. Its activity can be regulated by phosphorylation. Its unphosphorylated state is a high molecular weight aggregated form (100-800kDa) composed of up to 24 subunits, which forms as a result of multiple interactions within the ACD, and is required for chaperone function and resistance to oxidative stress. Upon phosphorylation these large aggregates rapidly disassociate to smaller oligomers and chaperone activity is modified. High constitutive levels of Hsp27 have been detected in various cancer cells, in particular those of carcinoma origin. Over-expression of Hsp27 has a protective effect against various diseases-processes, including Huntington's disease. Mutations in Hsp27 have been associated with a form of distal hereditary motor neuropathy type II and Charcot-Marie-Tooth disease type 2.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06475     4 EIRQTADRWKVSLDVNHFAPEELVVKTKDGVVEITGKHEEKQDEHGFVSRCFTRKYTLPPGVDPTAVTSSLSPDGILTVE 83

                  ..
gi 1392113100 106 GP 107
Cdd:cd06475    84 AP 85

Alpha crystallin domain (ACD) found in mammalian small heat shock protein (sHsp) HspB2/heat shock 27kDa protein 2 and similar proteins. sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. HspB2 is preferentially and constitutively expressed in skeletal muscle and heart. HspB2 shows homooligomeric activity and forms aggregates in muscle cytosol. Although its expression is not induced by heat shock, it redistributes to the insoluble fraction in response to heat shock. In the mouse heart, HspB2 plays a role in maintaining energetic balance, by protecting cardiac energetics during ischemia/reperfusion, and allowing for increased work during acute inotropic challenge. hHspB2 [previously also known as myotonic dystrophy protein kinase (DMPK) binding protein (MKBP)] is selectively up-regulated in skeletal muscles from myotonic dystrophy patients. The ACD of hHspB2 binds the DMPK kinase domain. In vitro, hHspB2 enhances the kinase activity of DMPK and confers thermoresistance. The hHspB2 gene lies less than 1kb from the 5 prime end of the related alphaB (HspB4)-crystallin gene, with the opposite transcription direction. These two genes may share regulatory elements for their expression.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  26 QVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFC 105
Cdd:cd06476     1 QVESEDDKYQVFLDVCHFTPDEITVRTVDNLLEVSARHPQRMDRHGFVSREFTRTYILPMDVDPLLVRASLSHDGILCIQ 80

                  ...
gi 1392113100 106 GPK 108
Cdd:cd06476    81 APR 83

This domain family includes the alpha-crystallin domain (ACD) of alpha-crystallin-type small heat shock proteins (sHsps) and a similar domain found in p23-like proteins. sHsps are small stress induced proteins with monomeric masses between 12 -43 kDa, whose common feature is this ACD. sHsps are generally active as large oligomers consisting of multiple subunits, and are believed to be ATP-independent chaperones that prevent aggregation and are important in refolding in combination with other Hsps. p23 is a cochaperone of the Hsp90 chaperoning pathway. It binds Hsp90 and participates in the folding of a number of Hsp90 clients including the progesterone receptor. p23 also has a passive chaperoning activity. p23 in addition may act as the cytosolic prostaglandin E2 synthase. Included in this family is the p23-like C-terminal CHORD-SGT1 (CS) domain of suppressor of G2 allele of Skp1 (Sgt1) and the p23-like domains of human butyrate-induced transcript 1 (hB-ind1), NUD (nuclear distribution) C, Melusin, and NAD(P)H cytochrome b5 (NCB5) oxidoreductase (OR).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1392113100  30 DRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHnERQDDHGYISREFHRRYRLPSNVDQSALSCSLSaDGMLTFCGPK 108
Cdd:cd00298     4 TDDEVVVTVDLPGVKKEDIKVEVEDNVLTISGKR-EEEEERERSYGEFERSFELPEDVDPEKSKASLE-NGVLEITLPK 80

Alpha crystallin domain (ACD) found in mammalian small heat shock protein (sHsp) HspB9 and similar proteins. sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. Human (h) HspB9 is expressed exclusively in the normal testis and in various tumor samples and is a cancer/testis antigen. hHspB9 interacts with TCTEL1 (T-complex testis expressed protein -1), a subunit of dynein. hHspB9 and TCTEL1 are co-expressed in similar cells within the testis and in tumor cells. Included in this group is Xenopus Hsp30, a developmentally-regulated heat-inducible molecular chaperone.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1392113100  32 DKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHG----YISREFHRRYRLPSNVDQSALSCSLSADGMLTFCGP 107
Cdd:cd06481     7 EGFSLKLDVRGFSPEDLSVRVDGRKLVVTGKREKKNEDEKgsfsYEYQEFVREAQLPEHVDPEAVTCSLSPSGHLHIRAP 86

Small heat shock protein IbpA, HSP20 family [Posttranslational modification, protein turnover, chaperones];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1392113100  32 DKFVIFLDVKHFSPEDLTVKVQDDFVEIHG--KHNERQDDHGYISRE-----FHRRYRLPSNVDQSALSCSLSaDGMLT 103
Cdd:COG0071     9 DAYVITADLPGVDKEDIDVTVEGNVLTISGerKEEEEEEGENYLRRErrygsFERSFTLPDDVDVDKIEASYE-NGVLT 86

Alpha-crystallin domain (ACD) found in Escherichia coli inclusion body-associated proteins IbpA and IbpB, and similar proteins. IbpA and IbpB are 16 kDa small heat shock proteins (sHsps). sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. IbpA and IbpB are produced during high-level production of various heterologous proteins, specifically human prorenin, renin and bovine insulin-like growth factor 2 (bIGF-2), and are strongly associated with inclusion bodies containing these heterologous proteins. IbpA and IbpB work as an integrated system to stabilize thermally aggregated proteins in a disaggregation competent state. The chaperone activity of IbpB is also significantly elevated as the temperature increases from normal to heat shock. The high temperature results in the disassociation of 2-3-MDa IbpB oligomers into smaller approximately 600-kDa structures. This elevated activity seen under heat shock conditions is retained for an extended period of time after the temperature is returned to normal. IbpA also forms multimers.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1392113100  27 VRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDD-----H-GYISREFHRRYRLPSNV 87
Cdd:cd06470     6 EKTGENNYRITLAVAGFSEDDLEIEVENNQLTVTGKKADEENEereylHrGIAKRAFERSFNLADHV 72

Alpha crystallin domain (ACD) found in mammalian small heat shock protein (sHsp) HspB10, also known as sperm outer dense fiber protein (ODFP), and similar proteins. sHsps are molecular chaperones that suppress protein aggregation and protect against cell stress, and are generally active as large oligomers consisting of multiple subunits. Human (h) HspB10 occurs exclusively in the axoneme of sperm cells and may have a cytoskeletal role.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1392113100  30 DRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHG---YISREFHRRYRLPSNVDQSALSCSLSAD 99
Cdd:cd06482     6 DSSNVLASVDVCGFEPDQVKVKVKDGKVQVSAERENRYDCLGskkYSYMNICKEFSLPPGVDEKDVTYSYGLG 78