The group of Fulvia Bono published a structure-to-functional analysis of the bicoid mRNA-localization factor Exuperantia (Exu) from Drosophila. Their crystal structure shows that Exu forms a dimer and that each subunit consists of a catalytically inactive 3’-5’ EXO domain and a SAM domain. Both domains are required for binding to a highly structured region in the 3’UTR of the bicoid transcript. Thus, Exu is a non-canonical RNA-binding protein.
Lazzaretti D, Veith K, Kramer K, Basquin C, Urlaub H, Irion U, Bono F.
The bicoid mRNA localization factor Exuperantia is an RNA-binding pseudonuclease.
Nat Struct Mol Biol. 2016 Jul 4. doi: 10.1038/nsmb.3254.
The group of Anne Ephrussi used a very different approach to study mRNA localization in the fruit fly. In this study, all RNA-interacting proteins were mapped before and after maternal-to-zygotic transition of early embryogenesis. From the over 500 detected factors about half of them had not been described before as RNA-binding proteins. Furthermore the comparison of both datasets indicates that the RNA-bound proteome is highly dynamic during early developmental stages.
Sysoev VO, Fischer B, Frese CK, Gupta I, Krijgsveld J, Hentze MW, Castello A, Ephrussi A.
Global changes of the RNA-bound proteome during the maternal-to-zygotic transition in Drosophila.
Nat Commun. 2016 Jul 5;7:12128. doi: 10.1038/ncomms12128.