CLN2/YPL256C Summary Help

Standard Name CLN2 1
Systematic Name YPL256C
Feature Type ORF, Verified
Description G1 cyclin involved in regulation of the cell cycle; activates Cdc28p kinase to promote the G1 to S phase transition; late G1 specific expression depends on transcription factor complexes, MBF (Swi6p-Mbp1p) and SBF (Swi6p-Swi4p); CLN2 has a paralog, CLN1, that arose from the whole genome duplication (1, 2, 3, 4, 5 and see Summary Paragraph)
Name Description CycLiN 1
Chromosomal Location
ChrXVI:66614 to 64977 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All CLN2 GO evidence and references
  View Computational GO annotations for CLN2
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 115 genes
Classical genetics
Large-scale survey
370 total interaction(s) for 204 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 37
  • Affinity Capture-RNA: 2
  • Affinity Capture-Western: 34
  • Biochemical Activity: 14
  • Co-localization: 1
  • PCA: 1
  • Protein-peptide: 1
  • Protein-RNA: 1
  • Reconstituted Complex: 5
  • Two-hybrid: 5

Genetic Interactions
  • Dosage Growth Defect: 6
  • Dosage Lethality: 42
  • Dosage Rescue: 30
  • Negative Genetic: 83
  • Phenotypic Enhancement: 11
  • Phenotypic Suppression: 16
  • Positive Genetic: 9
  • Synthetic Growth Defect: 28
  • Synthetic Lethality: 31
  • Synthetic Rescue: 13

Expression Summary
Length (a.a.) 545
Molecular Weight (Da) 61,696
Isoelectric Point (pI) 5.68
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXVI:66614 to 64977 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 1996-07-31 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1638 66614..64977 1996-07-31 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000006177

CLN2 encodes a G1 cyclin involved in regulation of the cell cycle. Progression through the cell cycle is a carefully regulated process that is conserved throughout eukaryotes. Periodic activation of cyclin-dependent kinases (CDKs) are required for this process; the critical CDK involved in cell cycle progression in yeast is Cdc28p.

Cyclins are the regulatory subunits that activate CDKs at the appropriate time in the cell cycle; they were named for their cyclical accumulation during particular phases of the cell cycle (6). Distinct CDK-cyclin complexes are required for progression through different stages of the cell cycle (7). CLN1, CLN2, and CLN3 encode the yeast cyclins involved in the G1 to S phase transition. CLN1 and CLN2 are closely related genes with overlapping functions; both are expressed in late G1 phase when they associate with Cdc28p to activate its kinase activity (4, 8). Accumulation of CLN1 and CLN2 mRNA in late G1 is dependent on two transcription factor complexes, MBF (Swi6p-Mbp1p) and SBF (Swi6p-Swi4p), which bind to MCB and SCB promoter elements, respectively (2, 3). In addition, Cln3p has been shown to activate CLN1 and CLN2 transcription while the G2 cyclins Clb1p, Clb2p, Clb3p, and Clb4p inhibit it (9, 10). Pheromone-induced cell cycle arrest is caused by the inhibition of the Cdc28p-Cln1p and Cdc28p-Cln2p complexes by the Far1 protein (11, 12). An excellent review by Lew et al. describes cell cycle control in S. cerevisiae in detail (7).

Last updated: 1999-12-16 Contact SGD

References cited on this page View Complete Literature Guide for CLN2
1) Hadwiger JA, et al.  (1989) A family of cyclin homologs that control the G1 phase in yeast. Proc Natl Acad Sci U S A 86(16):6255-9
2) Cross FR, et al.  (1994) Role of Swi4 in cell cycle regulation of CLN2 expression. Mol Cell Biol 14(7):4779-87
3) Stuart D and Wittenberg C  (1994) Cell cycle-dependent transcription of CLN2 is conferred by multiple distinct cis-acting regulatory elements. Mol Cell Biol 14(7):4788-801
4) Wittenberg C, et al.  (1990) G1-specific cyclins of S. cerevisiae: cell cycle periodicity, regulation by mating pheromone, and association with the p34CDC28 protein kinase. Cell 62(2):225-37
5) Byrne KP and Wolfe KH  (2005) The Yeast Gene Order Browser: combining curated homology and syntenic context reveals gene fate in polyploid species. Genome Res 15(10):1456-61
6) Evans T, et al.  (1983) Cyclin: a protein specified by maternal mRNA in sea urchin eggs that is destroyed at each cleavage division. Cell 33(2):389-96
7) Lew DJ, et al.  (1997) "Cell cycle control in Saccharomyces cerevisiae." Pp. 607-695 in The Molecular and Cellular Biology of the Yeast Saccharomyces: Cell Cycle and Cell Biology, edited by Pringle JR, Broach JR and Jones EW. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press
8) Nasmyth K  (1996) At the heart of the budding yeast cell cycle. Trends Genet 12(10):405-12
9) Tyers M, et al.  (1993) Comparison of the Saccharomyces cerevisiae G1 cyclins: Cln3 may be an upstream activator of Cln1, Cln2 and other cyclins. EMBO J 12(5):1955-68
10) Amon A, et al.  (1993) Mechanisms that help the yeast cell cycle clock tick: G2 cyclins transcriptionally activate G2 cyclins and repress G1 cyclins. Cell 74(6):993-1007
11) Chang F and Herskowitz I  (1990) Identification of a gene necessary for cell cycle arrest by a negative growth factor of yeast: FAR1 is an inhibitor of a G1 cyclin, CLN2. Cell 63(5):999-1011
12) Tyers M and Futcher B  (1993) Far1 and Fus3 link the mating pheromone signal transduction pathway to three G1-phase Cdc28 kinase complexes. Mol Cell Biol 13(9):5659-69