UMMS Affiliation

Department of Cell and Developmental Biology

Publication Date


Document Type



Cell Biology | Developmental Biology | Molecular Biology | Molecular Genetics | Musculoskeletal Diseases | Nervous System Diseases


In amphibian oocytes, the maternal nuclear factor NF7 associates with the elongating pre-mRNAs present on the numerous lateral loops of the lampbrush chromosomes. Here, we have purified NF7 from an oocyte extract by using a combination of ion-exchange chromatography and gel filtration chromatography and demonstrated for the first time that nucleoplasmic NF7 exists primarily as free homotrimers. We confirmed the in vivo homotrimerization of NF7 by using a glutaraldehyde cross-linking assay, and we further showed that it only requires the coiled-coil domain of the NF7 tripartite motif/RBCC motif. Interestingly, we also obtained evidence that NF7 is recruited to the nucleus as a homotrimer, and expression of several mutated forms of NF7 in oocytes demonstrated that both the coiled coil and B box of NF7 are required for its chromosomal association. Together, these data strongly suggest that the interaction of NF7 with the active transcriptional units of RNA polymerase II is mediated by a trimeric B box. Finally, and in agreement with a role for NF7 in pre-mRNA maturation, we obtained evidence supporting the idea that NF7 associates with Cajal bodies.

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DOI of Published Version



Beenders B, Jones PL, Bellini M. The tripartite motif of nuclear factor 7 is required for its association with transcriptional units. Mol Cell Biol. 2007 Apr;27(7):2615-24. DOI 10.1128/MCB.01968-06. Link to article on publisher's site

Journal/Book/Conference Title

Molecular and Cellular Biology


At the time of publication, Peter Jones was not yet affiliated with the University of Massachusetts Medical School.

Related Resources

Link to article in PubMed

PubMed ID