ste11 (S. pombe) review notes

UniProt P36631; PomBase SPBC32C12.02; 468 AA; HMG-box DNA-binding domain (residues 16-80).

Core biology

Ste11 is the master HMG-box transcription factor controlling sexual differentiation (mating/conjugation and meiotic entry) in fission yeast.

• PMID:1657709
• PMID:1657709
• PMID:1657709 -- TR-box. Supports double-stranded DNA binding (GO:0003690) and RNA Pol II cis-reg DNA binding (GO:0000978), and activator activity.

DNA binding mechanism / bending

• PMID:10867006
• PMID:10867006 -- supports GO:0044377 (cis-reg DNA binding, bending).

Recruitment / cooperativity with Mat1-Mc (M-cell specific genes)

• PMID:9233811
• PMID:9233811 -- WITH = PomBase:SPBC23G7.09 (mat1-Mc). Supports protein binding / RNA Pol II transcription regulator complex annotations from this paper.

Target genes

• mat1-Pm / mat1-Pc: PMID:7975894
• mfm M-factor genes: PMID:8196631
• rgs1: PMID:11554925
• dmc1/rad24 bicistronic meiotic transcript: PMID:10908327
• ste8/STE11(Sc): PMID:1435723 -- this paper is about S. pombe ste8 (=byr2) and S. cerevisiae STE11 kinase, NOT directly about the HMG TF ste11. However GOA cites it for "positive regulation of transcription by RNA Pol II" for ste11 P36631. The paper shows mat1-Pm induction requires the pheromone signal transduction. Annotation is borderline; ste11 (TF) is the activator of mat1-Pm. Keep but note the paper's primary subject is ste8.

Regulation (negative)

• Pat1/Ran1 kinase phosphorylates Ste11 (inhibitory): PMID:8945514.
• MAPK Spk1 phosphorylates and binds Ste11 (positive, pheromone pathway): PMID:15713656 WITH = PomBase:SPAC31G5.09c (spk1). Also PMID:15713656
• PKA + TOR pathways block Ste11 nuclear accumulation: PMID:20634885 and PMID:20634885. Supports both nucleus AND cytoplasm localization (shuttling).
• Tor2-Mei2-Ste11 complex: PMID:17046992 Supports GO:0034064 part_of Tor2-Mei2-Ste11 complex (IDA).
• Rad24 (14-3-3) binds phospho-Ste11: PMID:37788281 supports nucleoplasm activity.

Upstream activation

• Rst2 (Zn-finger) activates ste11 transcription; ste11 autoregulates: PMID:10982411

Localization (CC)

• Nucleus + cytoplasm shuttling, nuclear accumulation on starvation/pheromone: [PMID:20634885 above]; high-throughput nucleus/cytosol PMID:16823372; PKA mutants show nuclear Ste11 PMID:21879336.

Annotation decisions summary

• MF DNA-binding TF activity / activator / sequence-specific Pol II DNA binding / dsDNA binding / bending: ACCEPT (core).
• BP regulation/positive regulation of transcription by Pol II, positive regulation of conjugation with cellular fusion: ACCEPT (core).
• CC nucleus / nucleoplasm: ACCEPT (core action location). cytoplasm/cytosol: KEEP_AS_NON_CORE (shuttling reservoir; not where it acts as TF).
• GO:0005515 protein binding (x2): MODIFY/REMOVE-style. CLAUDE.md says avoid bare "protein binding". Mark for more informative term where possible. WITH mat1-Mc -> recruited into Pol II regulator complex (already captured by GO:0090575). WITH spk1 -> it is the kinase substrate relationship. Use MARK_AS_OVER_ANNOTATED / replace not feasible without good MF term; recommend NEW protein-binding-with-context not available -> mark as over-annotated bare protein binding.
• GO:0034064 Tor2-Mei2-Ste11 complex: ACCEPT (well documented).
• GO:0090575 Pol II transcription regulator complex: ACCEPT (Ste11 is a Pol II TF in a regulator complex with Mat1-Mc).