SIC1/YLR079W Protein Information

Standard Name	Sic1p
Systematic Name	Ylr079wp
Alias	Sdb25p
ORF Classification	Verified
Description	Cyclin-dependent kinase inhibitor (CKI); inhibitor of Cdc28-Clb kinase complexes that controls G1/S phase transition, preventing premature S phase and ensuring genomic integrity; phosphorylation targets Sic1p for SCF(CDC4)-dependent turnover; functional homolog of mammalian Kip1 (1, 2, 3, 4, 5, 6, 7, 8, 9)
Name Description	Substrate/Subunit Inhibitor of Cyclin-dependent protein kinase 3

Experimental Data
Molecules/cell	768 10

Predicted Sequence	Formatted Sequence or sequence in FASTA format
Length (a.a.)	284
Molecular Weight (Da)	32,223
Isoelectric Point (pI)	8.94

Click on image for expanded interactive view

Post-translational Modifications	PhosphoGRID \| PhosphoPep Database
Domains/motifs	See the graphical view and list of proteins that share domains/motifs in common with Sic1p (InterPro)
Physical Interactions	There are 117 total physical interactions (BioGRID)
Homologs	PDB Homologs \| BLASTP \| BLASTP v. fungi \| Fungal Alignment \| Synteny Viewer
External Sequence Databases	EBI: UPI0000052F58 \| P38634 MIPS: YLR079W NCBI: 1256881 \| 1360441 \| 385867624 \| 460996 \| 515642 \| 585990 \| 6323108 \| NP_013180.1 GenBank/EMBL/DDBJ: DAA09395.1 \| U01300 \| U53880 \| X78309 \| Z73251

Amino Acid Sequence (or in FASTA format)
1 MTPSTPPRSR GTRYLAQPSG NTSSSALMQG QKTPQKPSQN LVPVTPSTTK 51 SFKNAPLLAP PNSNMGMTSP FNGLTSPQRS PFPKSSVKRT LFQFESHDNG 101 TVREEQEPLG RVNRILFPTQ QNVDIDAAEE EEEGEVLLPP SRPTSARQLH 151 LSLERDEFDQ THRKKIIKDV PGTPSDKVIT FELAKNWNNN SPKNDARSQE 201 SEDEEDIIIN PVRVGKNPFA SDELVTQEIR NERKRAMLRE NPDIEDVITY 251 VNKKGEVVEK RRLTDEEKRR FKPKALFQSR DQEH*

Amino Acid Sequence (or in FASTA format)

       1  MTPSTPPRSR GTRYLAQPSG NTSSSALMQG QKTPQKPSQN LVPVTPSTTK
      51  SFKNAPLLAP PNSNMGMTSP FNGLTSPQRS PFPKSSVKRT LFQFESHDNG
     101  TVREEQEPLG RVNRILFPTQ QNVDIDAAEE EEEGEVLLPP SRPTSARQLH
     151  LSLERDEFDQ THRKKIIKDV PGTPSDKVIT FELAKNWNNN SPKNDARSQE
     201  SEDEEDIIIN PVRVGKNPFA SDELVTQEIR NERKRAMLRE NPDIEDVITY
     251  VNKKGEVVEK RRLTDEEKRR FKPKALFQSR DQEH*

external links for Sic1p

Homologs	Interaction Resources	Protein databases/Other	Localization Resources
BLASTP (NCBI)	BioGRID	SCOP Superfamily	YPL+
Ashbya (AGD)	BOND	GPMdb (Mass Spec.)	YeastGFP
YGOB	BioPIXIE	MIPS	YeastRC Public Image Repository
YOGY	CYC2008 (complexes)	Pfam domains
	Complexome
	DIP
	GeneMANIA
	YeastRC Two-Hybrid (Seattle)

References cited on this page View Complete Literature Guide for Sic1p

1)	Feldman RM, et al. (1997) A complex of Cdc4p, Skp1p, and Cdc53p/cullin catalyzes ubiquitination of the phosphorylated CDK inhibitor Sic1p. Cell 91(2):221-30
2)	Schwob E, et al. (1994) The B-type cyclin kinase inhibitor p40SIC1 controls the G1 to S transition in S. cerevisiae. Cell 79(2):233-44
3)	Nugroho TT and Mendenhall MD (1994) An inhibitor of yeast cyclin-dependent protein kinase plays an important role in ensuring the genomic integrity of daughter cells. Mol Cell Biol 14(5):3320-8
4)	Donovan JD, et al. (1994) P40SDB25, a putative CDK inhibitor, has a role in the M/G1 transition in Saccharomyces cerevisiae. Genes Dev 8(14):1640-53
5)	Mendenhall MD (1993) An inhibitor of p34CDC28 protein kinase activity from Saccharomyces cerevisiae. Science 259(5092):216-9
6)	Skowyra D, et al. (1997) F-box proteins are receptors that recruit phosphorylated substrates to the SCF ubiquitin-ligase complex. Cell 91(2):209-19
7)	Verma R, et al. (1997) Phosphorylation of Sic1p by G1 Cdk required for its degradation and entry into S phase. Science 278(5337):455-60
8)	Nash P, et al. (2001) Multisite phosphorylation of a CDK inhibitor sets a threshold for the onset of DNA replication. Nature 414(6863):514-21
9)	Barberis M, et al. (2005) The yeast cyclin-dependent kinase inhibitor Sic1 and mammalian p27Kip1 are functional homologues with a structurally conserved inhibitory domain. Biochem J 387(Pt 3):639-47
10)	Ghaemmaghami S, et al. (2003) Global analysis of protein expression in yeast. Nature 425(6959):737-41