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2  structures 930  species 0  interactions 2301  sequences 35  architectures

Family: Cnn_1N (PF07989)

Summary: Centrosomin N-terminal motif 1

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Centrosomin N-terminal motif 1 Provide feedback

This domain has been identified in two microtubule associated proteins in Schizosaccharomyces pombe, Mto1 and Pcp1. Mto1 has been identified in association with spindle pole body and non-spindle pole body microtubules [1]. The pericentrin homologue Pcp1 is also associated with the fungal centrosome or spindle pole body (SPB) [2]. Members of this family have been named centrosomins, and are an essential mitotic centrosome component required for assembly of all other known pericentriolar matrix proteins in order to achieve microtubule-organising activity in fission yeast [3]. Cnn_1N is a short conserved motif towards the N-terminus. Motif 1 is found to be necessary for proper recruitment of gamma-tubulin, D-TACC (the homolog of vertebrate transforming acidic coiled-coil proteins [TACC]), and Minispindles (Msps) to embryonic centrosomes but is not required for assembly of other centrosome components including Aurora A kinase and CP60 in Drosophila [4].

Literature references

  1. Venkatram S, Tasto JJ, Feoktistova A, Jennings JL, Link AJ, Gould KL; , Mol Biol Cell 2004;15:2287-2301.: Identification and characterization of two novel proteins affecting fission yeast gamma-tubulin complex function. PUBMED:15004232 EPMC:15004232

  2. Flory MR, Morphew M, Joseph JD, Means AR, Davis TN; , Cell Growth Differ. 2002;13:47-58.: Pcp1p, an Spc110p-related calmodulin target at the centrosome of the fission yeast Schizosaccharomyces pombe. PUBMED:11864908 EPMC:11864908

  3. Sawin KE, Lourenco PC, Snaith HA;, Curr Biol. 2004;14:763-775.: Microtubule nucleation at non-spindle pole body microtubule-organizing centers requires fission yeast centrosomin-related protein mod20p. PUBMED:15120067 EPMC:15120067

  4. Zhang J, Megraw TL;, Mol Biol Cell. 2007;18:4037-4049.: Proper recruitment of gamma-tubulin and D-TACC/Msps to embryonic Drosophila centrosomes requires Centrosomin Motif 1. PUBMED:17671162 EPMC:17671162

Internal database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR012943

This domain (Cnn_1N) is a short conserved motif found in the N-terminal of a group of centrosome or spindle pole body (SPB) associated proteins, including Mto1 and Pcp1 from S. pombe [ PUBMED:15004232 , PUBMED:11864908 ], centrosomin from flies [ PUBMED:10357928 , PUBMED:24656740 ] and myomegalin/CDK5RAP2 from mammals [ PUBMED:18042621 , PUBMED:11134006 ].

In Drosophila, centrosomin (Cnn) is an essential mitotic centrosome component required for assembly of all other known pericentriolar matrix (PCM) proteins to achieve microtubule-organising activity at mitosis. The Cnn_1N domain (motif 1 of Cnn) is necessary for proper recruitment of gamma-tubulin, D-TACC (the homologue of vertebrate transforming acidic coiled-coil proteins [TACC]), and Minispindles (Msps) to embryonic centrosomes but is not required for assembly of other centrosome components including Aurora A kinase and CP60 in Drosophila [ PUBMED:17671162 ].

Gene Ontology

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Domain organisation

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Curation and family details

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Seed source: Pfam-B_45034 (release 16.0)
Previous IDs: Spindle_assoc; Microtub_assoc;
Type: Coiled-coil
Sequence Ontology: SO:0001080
Author: Mistry J , Wood V
Number in seed: 80
Number in full: 2301
Average length of the domain: 73.20 aa
Average identity of full alignment: 37 %
Average coverage of the sequence by the domain: 5.54 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 28.5 28.5
Trusted cut-off 28.6 28.5
Noise cut-off 28.4 28.4
Model length: 73
Family (HMM) version: 13
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Species distribution

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Archea Archea Eukaryota Eukaryota
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Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Cnn_1N domain has been found. There are 2 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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trRosetta Structure

The structural model below was generated by the Baker group with the trRosetta software using the Pfam UniProt multiple sequence alignment.

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Improved protein structure prediction using predicted inter-residue orientations. Jianyi Yang, Ivan Anishchenko, Hahnbeom Park, Zhenling Peng, Sergey Ovchinnikov, David Baker Proceedings of the National Academy of Sciences Jan 2020, 117 (3) 1496-1503; DOI: 10.1073/pnas.1914677117;