Homologous Superfamily

Knr4/Smi1-like domain superfamily (IPR037883)

Short name: Knr4/Smi1-like_sf

Overlapping entries


This domain superfamily is found in the yeast cell wall assembly regulator Smi1 (also known as Knr4) [PMID: 7937796, PMID: 8289782].

Saccharomyces cerevisiae Knr4 has a regulatory role in chitin deposition and in cell wall assembly [PMID: 10206705]. It 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 [PMID: 12185498, PMID: 12823808]. Knr4 also interacts with the tyrosine-tRNA synthetase protein encoded by Tys1 and is involved in sporulation process [PMID: 11410349].

Proteins containing this domain also include the animal F-box only protein 3 (FBXO3). In humans, FBXO3 is a substrate recognition component of the SCF (SKP1-CUL1-F-box protein)-type E3 ubiquitin ligase complex [PMID: 18809579].

Interestingly, Smi1/Knr4 homologues from bacteria are potential immunity proteins in a subset of these contact-dependent inhibitory toxin systems [PMID: 21306995].

Note: previously reported evidence that Knr4 may interact with nuclear matrix-association region [PMID: 8516310] may be due to an artefact [PMID: 10206705].

This domain superfamily is also found in the Syd protein which interacts with the SecY protein.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.