These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Co-occupancy of two Pumilio molecules on a single hunchback NRE.
    Author: Gupta YK, Lee TH, Edwards TA, Escalante CR, Kadyrova LY, Wharton RP, Aggarwal AK.
    Journal: RNA; 2009 Jun; 15(6):1029-35. PubMed ID: 19372537.
    Abstract:
    Pumilio controls a number of processes in eukaryotes, including the translational repression of hunchback (hb) mRNA in early Drosophila embryos. The Pumilio Puf domain binds to a pair of 32 nucleotide (nt) Nanos response elements (NRE1 and NRE2) within the 3' untranslated region of hb mRNA. Despite the elucidation of structures of human Pumilio Puf domain in complex with hb RNA elements, the nature of hb mRNA recognition remains unclear. In particular, the site that mediates regulation in vivo is significantly larger than the 8-10-nt RNA elements bound to single Puf molecules in crystal structures. Here we present biophysical and biochemical data that partially resolve the paradox. We show that each NRE is composed of two binding sites (Box A and Box B) and that two Puf domains can co-occupy a single NRE. The Puf domains have a higher affinity for the 3' Box B site than the 5' Box A site; binding to the intact NRE appears to be cooperative (at least in some experiments). We suggest that the 2 Pumilio:1 NRE complex is the functional regulatory unit in vivo.
    [Abstract] [Full Text] [Related] [New Search]