TABLE 6.

Transcriptional CDKs in S. pombe.

Cyclin‐dependent kinase	Binding partner	Roles in cell cycle	Roles in transcription	Selected additional roles
Mc6	Mcs2	CAK activity (for Cdc2) (Buck et al., 1995; Damagnez et al., 1995; Lee et al., 1999; Saiz & Fisher, 2002) Inhibition impairs cytokinesis (Buck et al., 1995; Saiz & Fisher, 2002; Viladevall et al., 2009)	Part of TFIIH complex, important for early steps of pol II transcription (Booth et al., 2018; Spåhr et al., 2003; Viladevall et al., 2009) CTD kinase (S5, S7) (Amour et al., 2012; Booth et al., 2018; Viladevall et al., 2009) Recruits P‐TEFb to pol II by priming the CTD, leading to mRNA capping (Amour et al., 2012; Viladevall et al., 2009) Controls transcription of cell‐cycle periodic genes through interactions with Sep1 (Lee et al., 2005)	Essential for growth (Damagnez et al., 1995; Molz et al., 1989; Saiz & Fisher, 2002)
Srb10	Srb11	Controls entry into mitosis by phosphorylating Fkh2 (Banyai et al., 2014; Szilagyi et al., 2012)	Part of mediator complex (Borggrefe et al., 2002; Samuelsen et al., 2003; Spåhr et al., 2003) Downregulates transcription in vitro (Spåhr et al., 2003) CTD kinase in vitro (S2, S5) (Borggrefe et al., 2002) Blocks mediator‐pol II interactions (Elmlund et al., 2006; Samuelsen et al., 2003) Acts as a global regulator of mitotic transcription (Banyai et al., 2014)	Downregulates expression of adhesins (Linder et al., 2008; Samuelsen et al., 2003)
SpCDK9	Pch1	Inhibition impairs cytokinesis (Viladevall et al., 2009)	Part of P‐TEFb complex, important for efficient elongation (Amour et al., 2012; Bartkowiak & Greenleaf, 2011; Guiguen et al., 2007; Parua et al., 2018; Viladevall et al., 2009) Regulates an early elongation checkpoint (Booth et al., 2018; Guiguen et al., 2007; Pei et al., 2003; Viladevall et al., 2009) CTD kinase (S2, S5, marginally S7) (Amour et al., 2012; Guiguen et al., 2007; Pei & Shuman, 2003) Phosphorylates Spt5 elongation factor (Amour et al., 2012; Booth et al., 2018; Parua et al., 2018; Pei & Shuman, 2003) Couples transcription to mRNA capping through its association with Pct1 and Pcm1 (Amour et al., 2012; Guiguen et al., 2007; Pei et al., 2003, 2006; Viladevall et al., 2009) Downregulates PP1 isoform Dis2 to create a termination switch (Parua et al., 2018) Upregulates histone H2B mono‐ubiquitylation (Sansó et al., 2012)	Essential for growth (Bimbó et al., 2005; Guiguen et al., 2007; Pei & Shuman, 2003) Implicated in DNA damage response (Gerber et al., 2008)
Lsk1	Lsc1	Upregulates the Septation Initiation Network to promote cytokinesis (Karagiannis et al., 2005; Karagiannis & Balasubramanian, 2007) Upregulates meiosis via stress‐responsive MAPK pathway (Coudreuse et al., 2010; Sukegawa et al., 2011)	Deletion causes minimal changes in transcription (Booth et al., 2018) CTD kinase (S2) (Booth et al., 2018; Karagiannis & Balasubramanian, 2007; Viladevall et al., 2009)	Downregulates sexual differentiation through interaction with Ste11 (Coudreuse et al., 2010; Sukegawa et al., 2011)