InterPro domain: IPR036915

This cyclin-like domain superfamily is found in cyclins, but it is also found as the core domain in transcription factor IIB (TFIIB) [ 1 ] and in the retinoblastoma tumour suppressor [ 2 ]. It consists of a duplication of a fold consisting of 5 helices, one of them surrounded by the others.

1. Crystal structure of a TFIIB-TBP-TATA-element ternary complex. Nature 377, 119-28
2. Structure of the retinoblastoma protein bound to adenovirus E1A reveals the molecular basis for viral oncoprotein inactivation of a tumor suppressor. Genes Dev. 21, 2711-6