Protein: Anillin-related medial ring protein mid1 (P78953)
Organism: Schizosaccharomyces pombe (strain 972 / ATCC 24843) (Fission yeast)
Function: Scaffold protein that anchors the contractile ring (CR) at the cell equator during cytokinesis. At the onset of mitosis, membrane-bound oligomers of mid1 assemble recruitment platforms for cytokinetic ring components at the medial cortex and stabilize the ring position during its compaction. Recruits dephosphorylated myo2, but also rng2, clp1 and cdc15 to nodes and to place cytokinetic nodes around the cell equator the medial cortex to promote the ring assembly in cooperation with F-actin. Necessary to stabilize the mitotic spindle perpendicular to the axis of cell division. Recruits also the cdr2 kinase to the CR.
Subcellular location: Nucleus {ECO:0000269|PubMed:10930468, ECO:0000269|PubMed:12186944, ECO:0000269|PubMed:19427212, ECO:0000269|PubMed:19474789, ECO:0000269|PubMed:9852154}. Cytoplasm, cell cortex {ECO:0000269|PubMed:10930468, ECO:0000269|PubMed:12186944, ECO:0000269|PubMed:16864655, ECO:0000269|PubMed:17077120, ECO:0000269|PubMed:17140794, ECO:0000269|PubMed:19427212, ECO:0000269|PubMed:19474789, ECO:0000269|PubMed:20434336, ECO:0000269|PubMed:22298427, ECO:0000269|PubMed:22427686, ECO:0000269|PubMed:22918954, ECO:0000269|PubMed:25501814, ECO:0000269|PubMed:9852154}. Cytoplasm, cytoskeleton {ECO:0000269|PubMed:19474789}. Note=During interphase, is exported from the nucleus and relocates to medial ring at the cell cortex (PubMed:12186944, PubMed:16864655, PubMed:19427212, PubMed:19474789). The localization to the cell division plane is regulated by the cell-end factor pom1 (PubMed:17077120, PubMed:17140794). First forms a diffuse cortical band during spindle formation and then coalesces into a ring before anaphase (PubMed:9852154). Binding to the medial cortex is facilitated by gef2 (PubMed:22298427). Phosphorylation by sid2 leads to removal from the cortex (PubMed:28605916). The cortical ER network restricts the lateral motion of mid1 and hence generates a permissive zone for actomyosin ring assembly precisely at the cell equator (PubMed:20434336). {ECO:0000269|PubMed:12186944, ECO:0000269|PubMed:16864655, ECO:0000269|PubMed:17077120, ECO:0000269|PubMed:17140794, ECO:0000269|PubMed:19427212, ECO:0000269|PubMed:19474789, ECO:0000269|PubMed:20434336, ECO:0000269|PubMed:22298427, ECO:0000269|PubMed:28605916, ECO:0000269|PubMed:9852154}.
Interaction partners:
- Cell division control protein 15
- Cell division control protein 12
- Ras GTPase-activating-like protein rng2
- Mitosis inducer protein kinase cdr2
- Serine/threonine-protein kinase plo1
- Myosin type-2 heavy chain 1
- Myosin regulatory light chain cdc4
- DYRK-family kinase pom1
- Myosin regulatory light chain 1
- Mitosis inducer protein blt1
Sequence:
MKEQEFSYREAKDVSLDSKGLENSFLSSPNREKTPLFFEGNSNETSGYDQTKNFTHGDGDMSLGNLSELNVATDLLESLDLRSMYMHGYGHLDSSFSSQHSPDNRKRMSSTSVFKRINSEEEGRIPSLTYSAGTMNSTSSSTASLKGADIVADYETFNPDQNLAELSFDRSKSSRKRAVEVAEFSRAKTMSPLEYTVQHPYQSHNELSTNPARARAGSVPNLARIPSDVKPVPPAHLSASSTVGPRILPSLPKDTTEDNPALERVETTASLDMDYKPLEPLAPIQEAPVEDTSEPFSSVPEATLDDSDISTESLRKKVLAKMEAKRISSGSSYASTLRKVYDFSELSLPTNGKDYDELYLQSSRNSEPEISTIINDSLQQENMDEDISATSIPKSQAAYGHGSVTYHEVPRYNLTSASVGYSISSQRGRIKSSSTIDNLSAILSSEDLRHPSMQPVPGTKRTYSNYCENEPNKSSQSLVSSESHNVEGWNYSETGTVGFYDPSAEISASIDELRQSTPVARDSELLSRAHSFDLNRLDLPSQDKSTSYEVPNGTENQSPRPVTSLGFVNETFFEEKPKAPLPLGRFYIHLNSILNISISEVHSPIKIIVNTPTQNMQLPWQAVNGNNRLDHDFAFHVDDNFKVSFMFLDIPIEDKSNGSKGVSATKDVSNGKPAETKSKARKFFDKLFNRRKKRKLNKAAAVENSKAKKSVVIKKVSGTATLNLGNVKDSCFGKAFNVEIPIISRGFLEAIPVKINSIGKRTLGNLTLTCLYIPELSVPEQELPFTLEQATMDLRHVRSNYLYNEGYLYRLEDSSIRRRFVVLRSKQLNFYAEKGGQYLDTFQLSKTVVSIPMVNFSEAVSNLGLVAGILATSVDRRHVQLFADSKKVCQKWLQVMNSRSFALDRGTEKLWLQEYVNFMA