An extensive homology search based on the sequence of the @entity375 protein @entity69086 (biogenesis of ribosomes in @entity1238 , YOL077c) revealed that it is a member of a superfamily of proteins sharing remarkable sequence similarities. Previous work on @entity69086 showed that this protein is involved in the process of ribosome biogenesis [Kaser et al., Biol. Chem. 382 (2001) 1637-1647]. @entity69086 is the founding member of one of the five existing eukaryotic subfamilies which are all present in @entity375 . Four of them are represented by one essential gene each and one family is represented by two closely related genes which can functionally replace each other but are essential together for survival. We created conditional alleles of four of the five genes which allowed us to study the effect of depletion of the respective proteins on the ribosome profiles of the strains. In this study we show that not only @entity69086 but also three additional superfamily members, namely YHR088w ( @entity69087 ), YKR081c ( @entity55592 ) and the homologous proteins @entity54004 (YHR066w)/ @entity54005 (YDR312w) are all involved in the multistep process of the assembly of the large ribosomal subunit. This agrees well with the fact that these three proteins, like @entity69086 , are located in the nucleolus. Moreover, all four proteins closely interact functionally, because all four mutants are suppressed by the same multicopy suppressor gene.

Functional analysis in XXXX of the Brix protein superfamily involved in the biogenesis of ribosomes.

@entity1238 :: ('8355', 'Species') :: ['Xenopus'] @entity54005 :: ('851907(Tax:4932)', 'Gene') :: ['Ssf2p'] @entity54004 :: ('856463(Tax:4932)', 'Gene') :: ['Ssf1p'] @entity69086 :: ('854078(Tax:4932)', 'Gene') :: ['Brx1p'] @entity69087 :: ('856488(Tax:4932)', 'Gene') :: ['Rpf1p'] @entity375 :: ('4932', 'Species') :: ['yeast'] @entity55592 :: ('853956(Tax:4932)', 'Gene') :: ['Rpf2p']
@entity375 :: (4932,Species) :: ['yeast']
