Identification of FBXO25-interacting proteins using an integrated proteomics approach

Author(s):Show less -

Teixeira, Felipe R. ; Yokoo, Sami ; Gartner, Carlos A. ^[1] ; Manfiolli, Adriana O. ; Baqui, Munira M. A. ; Assmann, Eliana M. ^[2] ; Maragno, Ana Leticia G. C. ; Yu, Huijun ^[3] ; de Lanerolle, Primal ^[3] ; Kobarg, Joerg ^[2] ; Gygi, Steven P. ^[1] ; Gomes, Marcelo Damario ^[4]

Affiliation

^[1] Harvard Univ, Harvard Med Sch, Dept Cell Biol, Boston, MA 02115 - USA

^[2] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Biociencias, Campinas, SP - Brazil

^[3] Univ Illinois, Dept Physiol & Biophys, Chicago, IL 60680 - USA

^[4] USP, Fac Med Ribeirao Preto, Dept Bioquim & Imunol, BR-14049900 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: PROTEOMICS; v. 10, n. 15, p. 2746-2757, JUL 2010.
• Web of Science Citations: 7

Abstract

FBXO25 is one of the 68 human F-box proteins that serve as specificity factors for a family of ubiquitin ligases composed of s-phase-kinase associated protein 1, really interesting new gene-box 1, Cullin 1, and F-box protein (SCF1) that are involved in targeting proteins for destruction across the ubiquitin proteasome system. We recently reported that the FBXO25 protein accumulates in novel subnuclear structures named FBXO25-associated nuclear domains (FAND). Combining two-step affinity purification followed by MS with a classical two-hybrid screen, we identified 132 novel potential FBXO25 interacting partners. One of the identified proteins, beta-actin, physically interacts through its N-terminus with FBXO25 and is enriched in the FBXO25 nuclear compartments. Inhibitors of actin polymerization promote a significant disruption of FAND, indicating that they are compartments influenced by the organizational state of actin in the nucleus. Furthermore, FBXO25 antibodies interfered with RNA polymerase II transcription in vitro. Our results open new perspectives for the understanding of this novel compartment and its nuclear functions. (AU)