InterPro : IPR002423

Name  Chaperonin Cpn60/TCP-1 Short Name  Cpn60/TCP-1
Type  Family Description  Partially folded polypeptide chains, either newly made by ribosomes or emerging from mature proteins unfolded by stress, run the risk of aggregating with one another to the detriment of the organism. Folding of newly synthesised polypeptides in the crowded cellular environment requires the assistance of molecular chaperone proteins, such as the large bacterial chaperonins GroEL and GroES. GroEL and GroES prevent aggregation by encapsulating individual chains within the so-called 'Anfinsen cage' provided by the GroEL-GroES complex, where they can fold in isolation from one another []. GroEL consists of two heptameric rings of identical ATPase subunits stacked back to back, containing a cage in each ring. Each subunit consists of three domains. The equatorial domain contains the nucleotide binding site and is connected by a flexible intermediate domain with the apical domain. The latter presents several hydrophobic amino-acid side chains at the top of the ring, orientated towards the cavity of the cage. These side chains are involved in binding either a partially folded polypeptide chain or a single molecule of GroES.The assembly of proteins has been thought to be the sole result of properties inherent in the primary sequence of polypeptides themselves. In some cases, however, structural information from other protein molecules is required for correct folding and subsequent assembly into oligomers []. These 'helper' molecules are referred to as molecular chaperones, a subfamily of which are the chaperonins [], which include 10 kDa and 60 kDa proteins. These are found in abundance in prokaryotes, chloroplasts and mitochondria. They are required for normal cell growth (as demonstrated by the fact that no temperature sensitive mutants for the chaperonin genes can be found in the temperature range 20 to 43 degrees centigrade []), and are stress-induced, acting to stabilise or protect disassembled polypeptides under heat-shock conditions [].The 10 kDa chaperonin (cpn10 - or groES in bacteria) exists as a ring-shaped oligomer of between 6 to 8 identical subunits, whereas the 60 kDa chaperonin (cpn60 - or groEL in bacteria) forms a structure comprising 2 stacked rings, each ring containing 7 identical subunits []. These ring structures assemble by self-stimulation in the presence of Mg2+-ATP. The cpn10 and cpn60 oligomers also require Mg2+-ATP in order to interact to form a functional complex, although the mechanism of this interaction is as yet unknown []. This chaperonin complex is essential for the correct folding and assembly of polypeptides into oligomeric structures, of which the chaperonins themselves are not a part []. The binding of cpn10 to cpn60 inhibits the weak ATPase activity of cpn60.The 60 kDa form of chaperonin is the immunodominant antigen of patients with Legionnaire's disease [], and is thought to play a role in the protection of the Legionella bacteria from oxygen radicals within macrophages. This hypothesis is based on the finding that the cpn60 gene is upregulated in response to hydrogen peroxide, a source of oxygen radicals. Cpn60 has also been found to display strong antigenicity in many bacterial species [], and has the potential for inducing immune protection against unrelated bacterial infections. The RuBisCO subunit binding protein (which has been implicated in the assembly of RuBisCO) and cpn60 have been found to be evolutionary homologues, the RuBisCO subunit binding protein having the C-terminal Gly-Gly-Met repeat found in all bacterial cpn60 sequences. Although the precise function of this repeat is unknown, it is thought to be important as it is also found in 70 kDa heat-shock proteins []. The crystal structure of Escherichia coliGroEL has been resolved to 2.8A []. The TCP-1 family of proteins act as molecular chaperones for tubulin, actin and probably some other proteins. They are weakly, but significantly, related to the cpn60/groEL chaperonin family.

Sequence Features

GO Displayer


InterPro protein domain ID --> Contigs



3 Child Features

Id Name Short Name Type
IPR017998 Chaperone tailless complex polypeptide 1 (TCP-1) Chaperone_TCP-1 Family
IPR001844 Chaperonin Cpn60 Chaprnin_Cpn60 Family
IPR028790 McKusick-Kaufman/Bardet-Biedl syndromes putative chaperonin MKKS Family

2 Contains

Id Name Short Name Type
IPR002194 Chaperonin TCP-1, conserved site Chaperonin_TCP-1_CS Conserved_site
IPR018370 Chaperonin Cpn60, conserved site Chaperonin_Cpn60_CS Conserved_site

0 Found In

0 Parent Features

7 Publications

First Author Title Year Journal Volume Pages
Gor D Cloning and nucleotide sequence of the Brucella abortus groE operon. 1992 Biochim Biophys Acta 1130 120-2
Hindersson P Sequence analysis of the Legionella micdadei groELS operon. 1991 FEMS Microbiol Lett 61 31-8
Schmidt A Cloning, sequencing, mapping, and transcriptional analysis of the groESL operon from Bacillus subtilis. 1992 J Bacteriol 174 3993-9
Hemmingsen SM Homologous plant and bacterial proteins chaperone oligomeric protein assembly. 1988 Nature 333 330-4
Braig K The crystal structure of the bacterial chaperonin GroEL at 2.8 A. 1994 Nature 371 578-86
Prasad TK cDNA clones encoding Arabidopsis thaliana and Zea mays mitochondrial chaperonin HSP60 and gene expression during seed germination and heat shock. 1992 Plant Mol Biol 18 873-85
Wang J Structural basis for GroEL-assisted protein folding from the crystal structure of (GroEL-KMgATP)14 at 2.0A resolution. 2003 J Mol Biol 327 843-55

To cite PlanMine, please refer to the following publication:

Rozanski, A., Moon, H., Brandl, H., Martín-Durán, J. M., Grohme, M., Hüttner, K., Bartscherer, K., Henry, I., & Rink, J. C.
PlanMine 3.0—improvements to a mineable resource of flatworm biology and biodiversity
Nucleic Acids Research, gky1070. doi:10.1093/nar/gky1070 (2018)