cln3∆ bck2∆ is inviable. So are the triple mutants cln3∆ bck2∆ sic1∆ and cln3∆ bck2∆ cdc6∆2-49.
cln3∆ bck2∆ sic1∆
cln3∆ bck2∆ cdc6∆2-49
Inviable, G1 arrest (Epstein & Cross, 1994)
Inviable (Wijnen & Futcher, 1999).
In all three mutants, SBF never activates, Cln2 is not synthesized. Neither SIC1 deletion nor CDC6∆2-49 can rescue the inviability of cln3∆ bck2∆.