Protein: DYRK-family kinase pom1 (EC 2.7.12.1) (Q09690)
Organism: Schizosaccharomyces pombe (strain 972 / ATCC 24843) (Fission yeast)
Function: Polarity factor involved in localization of polarized growth and cytokinesis. Forms an intracellular gradient that serves to measure cell length and control mitotic entry. Controls the timing of mitotic commitment by regulating the inhibitory impact of cdr1/cdr2 on wee1 activity. Directly phosphorylates the tail of cdr2 which inhibits cdr2 activation by ssp1. Cdr2 phosphorylation by pom1 also modulates cdr2 association with membranes and inhibits cdr2 interaction with mid1, reducing its clustering ability, possibly via the down-regulation of cdr2 kinase activity. Acts as a negative regulator of mid1 distribution, excluding mid1 from non-growing ends, which prevents division-septum assembly at the cell ends. The pom1 polar gradient also mediates mitotic entry by regulating cdk1. Plays an essential role in proper localization and phosphorylation of a GAP for cdc42, rga4, which ensures bipolar localization of GTP-bound, active cdc42 involved in F-actin formation. Phosphorylates multiple other substrates that function in polarized cell growth, including tea4, mod5, pal1, the Rho GAP rga7, and the Arf GEF syt22.
Subcellular location: Cell tip {ECO:0000269|PubMed:11230130, ECO:0000269|PubMed:11950884, ECO:0000269|PubMed:14663827}. Cell membrane {ECO:0000269|PubMed:21703453}; Peripheral membrane protein {ECO:0000269|PubMed:21703453}. Note=Forms an intracellular gradient that serves to measure cell length and control mitotic entry (PubMed:19474789, PubMed:19474792, PubMed:21703453, PubMed:22342545, PubMed:26150232). Localized to the cell division site at the time of cytokinesis (PubMed:14663827). Tea4 recruits pom1 to the cell cortex from where it then moves laterally at the plasma membrane, which it binds through a basic region exhibiting direct lipid interaction (PubMed:21703453). Pom1 autophosphorylates in this region to lower lipid affinity and promote membrane release (PubMed:21703453). Tea4 triggers pom1 plasma membrane association by promoting its dephosphorylation through the protein phosphatase dis2 (PubMed:21703453). {ECO:0000269|PubMed:14663827, ECO:0000269|PubMed:19474789, ECO:0000269|PubMed:19474792, ECO:0000269|PubMed:21703453, ECO:0000269|PubMed:22342545, ECO:0000269|PubMed:26150232}.
Interaction partners:
- Mitosis inducer protein kinase cdr2
- Tip elongation aberrant protein Tea4
- Tip elongation aberrant protein 1
- Anillin-related medial ring protein mid1
- Probable Rho-type GTPase-activating protein 4
- Serine/threonine-protein kinase plo1
- Tip elongation aberrant protein 3
- Cell division control protein 15
- Actin
- Uncharacterized WD repeat-containing protein C17D11.08
Sequence:
MGYLQSQKAVSLGDENTDALFKLHTSNRKSANMFGIKSELLNPSELSAVGSYSNDICPNRQSSSSTAADTSPSTNASNTNISFPEQEHKDELFMNVEPKGVGSSMDNHAITIHHSTGNGLLRSSFDHDYRQKNSPRNSIHRLSNISIGNNPIDFESSQQNNPSSLNTSSHHRTSSISNSKSFGTSLSYYNRSSKPSDWNQQNNGGHLSGVISITQDVSSVPLQSSVFSSGNHAYHASMAPKRSGSWRHTNFHSTSHPRAASIGNKSGIPPVPTIPPNIGHSTDHQHPKANISGSLTKSSSESKNLSTIQSPLKTSNSFFKELSPHSQITLSNVKNNHSHVGSQTKSHSFATPSVFDNNKPVSSDNHNNTTTSSQVHPDSRNPDPKAAPKAVSQKTNVDGHRNHEAKHGNTVQNESKSQKSSNKEGRSSRGGFFSRLSFSRSSSRMKKGSKAKHEDAPDVPAIPHAYIADSSTKSSYRNGKKTPTRTKSRMQQFINWFKPSKERSSNGNSDSASPPPVPRLSITRSQVSREPEKPEEIPSVPPLPSNFKDKGHVPQQRSVSYTPKRSSDTSESLQPSLSFASSNVLSEPFDRKVADLAMKAINSKRINKLLDDAKVMQSLLDRACIITPVRNTEVQLINTAPLTEYEQDEINNYDNIYFTGLRNVDKRRSADENTSSNFGFDDERGDYKVVLGDHIAYRYEVVDFLGKGSFGQVLRCIDYETGKLVALKIIRNKKRFHMQALVETKILQKIREWDPLDEYCMVQYTDHFYFRDHLCVATELLGKNLYELIKSNGFKGLPIVVIKSITRQLIQCLTLLNEKHVIHCDLKPENILLCHPFKSQVKVIDFGSSCFEGECVYTYIQSRFYRSPEVILGMGYGTPIDVWSLGCIIAEMYTGFPLFPGENEQEQLACIMEIFGPPDHSLIDKCSRKKVFFDSSGKPRPFVSSKGVSRRPFSKSLHQVLQCKDVSFLSFISDCLKWDPDERMTPQQAAQHDFLTGKQDVRRPNTAPARQKFARPPNIETAPIPRPLPNLPMEYNDHTLPSPKEPSNQASNLVRSSDKFPNLLTNLDYSIISDNGFLRKPVEKSRP