Antibodies to CCT - FocusOn 086

Introduction

Chaperones are proteins whose function is to assist other proteins in achieving proper folding. Many chaperones are heat shock proteins, that is, proteins expressed in response to elevated temperatures.

The reason for this behaviour is that protein folding is severely affected by heat, and therefore chaperones act to counteract the potential damage. Protein folding is an essential step in the expression of genetic information, and defects in this process lead to a variety of disease states.

There are several functionally and structurally distinct chaperone systems in the eukaryotic cytosol. The cytosolic chaperonin-containing t-complex polypeptide 1 (CCT) is a molecular chaperone that plays an important role in the folding of proteins in the eukaryotic cytosol. Actin, tubulin, and several other proteins are known to be folded by CCT, and an estimated 15% of newly translated proteins in mammalian cells are folded with the assistance of CCT. CCT differs from other chaperonin family proteins in its subunit composition, which consists of eight subunit species comprising the CCT 16-mer double-ring-like complex. CCT preferentially recognizes quasinative (or partially folded) intermediates, whereas its Escherichia coli homologue GroEL recognizes more unfolded intermediates, especially those displaying hydrophobic surfaces. Molecular evolutionary analyses have suggested that each subunit species has a specific function in addition to contributing to a common ATPase activity. Consistent with this view, it has been suggested that each subunit recognizes specific substrate proteins (or their parts) and that they collectively modulate the ATPase activity of the complex. The overall expression of CCT in mammalian cells is primarily dependent on cell growth, but each subunit exhibits an individual patterns of expression.

Antibody Panel to CCT

Acris Antibodies offers a range of monoclonal antibodies to different polypeptides of the CCT chaperonin molecule complex. These antibodies can be used in Western blot and / or Immunoprecipitation applications.

Fig.1: TCP1 antibody Cat.-No. AP16211PU-N staining of human lung lysate at 1 µg/ml (RIPA buffer, 35µg total protein per lane). Detected by western blot using chemiluminescence.

Fig.2: Western blot analysis of HeLa whole cell lysate (lane 1) and HeLa heat stressed whole cell lysate (lane 2) probed with rat anti mouse CCT alpha Cat.-No. SM2173P followed by F(ab')2 rabbit anti Rat IgG:HRP (Cat.-No. SP1021HRP).

Fig.3: Immunohistochemical staining of normal (left) and cancerous (right) colon tissue using TCP1 beta antibody Cat.-No. AM05385PU-N.

Fig.4: TCP1 epsilon antibody Cat.-No. AP31087PU-N staining of paraffin-embedded NCIN87 xenograft at 1/500 dilution.

Fig.5: Immunofluorescence analysis of paraformaldehyde-fixed HeLa, using TCP1 epsilon antibody Cat.-No. AP31087PU-N at 1/200 dilution.

Fig.6: Western blot analysis of HeLa whole cell lysate (lane 1) and HeLa heat stressed whole cell lysate (lane 2) probed with rat anti CCT Eta Cat.-No. SM2019P followed by F(ab')2 rabbit anti rat IgG:HRP (Cat.No. SP1021HRP).

Fig.7: TCP1 theta antibody Cat.-No. AP31086PU-N staining of A431 (A), H1299 (B), HeLa (C) whole cell lysates (30 µg) at 1/1000 dilution, 7.5% SDS PAGE.

Fig.8: Western blot analysis of HeLa whole cell lysate (lane 1) and HeLa heat stressed whole cell lysate (lane 2) probed with rat anti CCT theta Cat.-No. SM2017P followed by F(ab')2 rabbit anti rat IgG:HRP (Cat.-No. SP1021HRP).

Literature

Horwich AL, Fenton WA, Chapman E, Farr GWTwo families of chaperonin: physiology and mechanism.Annu Rev Cell Dev Biol. 2007;23:115-45.

Liu X, Lin CY, Lei M, Yan S, Zhou T, Erikson RL.CCT chaperonin complex is required for the biogenesis of functional Plk1.Mol Cell Biol. 2005 Jun 25(12):4993-5010.

Melville MW, McClellan AJ, Meyer AS, Darveau A, Frydman J.The Hsp70 and TRiC/CCT Chaperone Systems Cooperate In Vivo To Assemble the Von Hippel-Lindau Tumor Suppressor Complex.Molecular and Cellular Biology 2003 May 23(9): 3141-3151.

Kubota H.Function and regulation of cytosolic molecular chaperone CCT.Vitam Horm. 2002;65(3):13-31.

Llorca O, Martin-Benito J, Grantham J, Ritco-Vonsovici M, Willison KR, Carrascosa JL, Valpuesta JM.The 'sequential allosteric ring' mechanism in the eukaryotic chaperonin-assisted folding of actin and tubulin.EMBO J. 2001 Aug 1;20(15):4065-75.