Summary: SMI1 / KNR4 family (SUKH-1)
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SMI1 / KNR4 family (SUKH-1) Provide feedback
Proteins in this family are involved in the regulation of 1,3-beta-glucan synthase activity and cell-wall formation [1]. Genome contextual information showed that SMI1 are primary immunity proteins in bacterial toxin systems [3].
Literature references
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Enderlin CS, Selitrennikoff CP; , Proc Natl Acad Sci U S A. 1994;91:9500-9504.: Cloning and characterization of a Neurospora crassa gene required for (1,3) beta-glucan synthase activity and cell wall formation. PUBMED:7937796 EPMC:7937796
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Hong Z, Mann P, Brown NH, Tran LE, Shaw KJ, Hare RS, DiDomenico B; , Mol Cell Biol. 1994;14:1017-1025.: Cloning and characterization of KNR4, a yeast gene involved in (1,3)-beta-glucan synthesis. PUBMED:8289782 EPMC:8289782
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Zhang D, Iyer LM, Aravind L;, Nucleic Acids Res. 2011;39:4532-4552.: A novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and DNA viral systems. PUBMED:21306995 EPMC:21306995
External database links
| PANDIT: | PF09346 |
| Pseudofam: | PF09346 |
| SYSTERS: | SMI1_KNR4 |
This tab holds annotation information from the InterPro database.
InterPro entry IPR018958
Proteins in this family are involved in the regulation of 1,3-beta-glucan synthase activity and cell-wall formation [PUBMED:7937796, PUBMED:8289782].
Yeast members of this family are involved in the regulation of cell wall assembly. Saccharomyces cerevisiae (Baker's yeast) protein KNR4 (SMI1) has a regulatory role in chitin deposition and in cell wall assembly [PUBMED:10206705]. It was originally identified as a regulator of chitin synthase expression (acting as a repressor) [PUBMED:10206705] and of 1,3-beta-glucan synthase levels [PUBMED:8289782]. It was shown to localise in patches at presumptive bud sites in unbudded cells and at the incipient bud site during bud emergence [PUBMED:10206705].
KNR4 is believed to connect the PKC1-SLT2 MAPK pathway with cell proliferation. It has been shown to interact with BCK2, a gene involved in cell cycle progression in S. cerevisiae (forming a complex) to allow PKC1 to coordinate the cell cycle (cell proliferation) with cell wall integrity [PUBMED:12185498, PUBMED:12823808]. PKC1 plays an essential role in cell wall integrity and cell proliferation through a bifurcated PKC1/mitogen-activated protein (MAP) kinase pathway. KNR4 also interacts with the tyrosine-tRNA synthetase protein encoded by TYS1 and is involved in sporulation process [PUBMED:11410349].
Note: previously reported evidence that KNR4 may interact with nuclear matrix-association region [PUBMED:8516310] may be due to an artefact [PUBMED:10206705].
Domain organisation
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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Pfam Clan
Alignments
We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...
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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.
| Seed (178) |
Full (1863) |
Representative proteomes | NCBI (2059) |
Meta (25) |
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| RP15 (137) |
RP35 (283) |
RP55 (391) |
RP75 (480) |
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| PP/heatmap | 1 | |||||||
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key:
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Format an alignment
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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.
| Seed (178) |
Full (1863) |
Representative proteomes | NCBI (2059) |
Meta (25) |
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|---|---|---|---|---|---|---|---|---|
| RP15 (137) |
RP35 (283) |
RP55 (391) |
RP75 (480) |
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| Raw Stockholm | ||||||||
| Gzipped | ||||||||
You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.
External links
MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.
HMM logo
HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...
Trees
This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
Note: You can also download the data file for the tree.
Curation and family details
This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.
Curation
| Seed source: | PSI2 target BIG_91 |
| Previous IDs: | DUF1988; |
| Type: | Domain |
| Author: | Bateman A |
| Number in seed: | 178 |
| Number in full: | 1863 |
| Average length of the domain: | 133.60 aa |
| Average identity of full alignment: | 15 % |
| Average coverage of the sequence by the domain: | 53.86 % |
HMM information
| HMM build commands: |
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
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| Model details: |
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| Model length: | 130 | ||||||||||||
| Family (HMM) version: | 5 | ||||||||||||
| Download: | download the raw HMM for this family |
Species distribution
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Interactions
There is 1 interaction for this family. More...
SMI1_KNR4Structures
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 SMI1_KNR4 domain has been found. There are 3 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 seqence.
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Archea
Eukaryota
Bacteria
Other sequences
Viruses
Unclassified
Viroids
Unclassified sequence