Progression of s phase. Also nucleolar protein implicated in rRNA processing and ribosome (60S) biogenesis - suggested link of replication to rDNA transcription?



ScYph1; pescadillo (higher organisms)

Molecular weight

Mouse – 68kDa

SC 68 (88 with polyribosomes) (1)

Biochemical properties



•Brct / 2 acidic clusters in n terminus/sumo attachment site (2)


Protein interactions


•Orc direct (and lots of others in big complex) (1)

•Rrb1 (3)



•T-ag/irs1 (4)



•SUMO (2) but not in yeast (1)



Cellular location and expression





•interphase  - nucleolar

mitosis – periphery of metaphase chromosomes

anaphase – nucleolus derived foci and prenucleolar bodies (5)

Other comments

•Mouse knockout lethal pre implantation (5)

•Knockdown cause chromosome segregation defects (3)

•Overexpression increases cell transformation (4)

•Zebra fish mutant small as proliferation down


Revised by


Last edited

13 April 08



1.    Du,Y.C. and Stillman,B. (2002) Yph1p, an ORC-interacting protein: potential links between cell proliferation control, DNA replication, and ribosome biogenesis. Cell 109, 835-848.

2.    Kinoshita,Y., Jarell,A.D., Flaman,J.M., Foltz,G., Schuster,J., Sopher,B.L., Irvin,D.K., Kanning,K., Kornblum,H.I., Nelson,P.S., Hieter,P. and Morrison,R.S. (2001) Pescadillo, a novel cell cycle regulatory protein abnormally expressed in malignant cells. J Biol Chem 276, 6656-6665.

3.    Killian,A., Le Meur,N., Sesboue,R., Bourguignon,J., Bougeard,G., Gautherot,J., Bastard,C., Frebourg,T. and Flaman,J.M. (2004) Inactivation of the RRB1-Pescadillo pathway involved in ribosome biogenesis induces chromosomal instability. Oncogene 23, 8597-8602.

4.    Maiorana,A., Tu,X., Cheng,G. and Baserga,R. (2004) Role of pescadillo in the transformation and immortalization of mammalian cells. Oncogene 23, 7116-7124.

5.    Lerch-Gaggl,A., Haque,J., Li,J., Ning,G., Traktman,P. and Duncan,S.A. (2002) Pescadillo is essential for nucleolar assembly, ribosome biogenesis, and mammalian cell proliferation. J Biol Chem 277, 45347-45355.