Characterization of a Trypanosoma brucei SR domain-containing protein bearing homology to cis-spliceosomal U1 70 kDa proteins.
The protozoan parasite Trypanosoma brucei relies on trans-splicing of a common spliced leader (SL) RNA to maturate mRNAs. Using the yeast two-hybrid system a protein (TSR1IP) was identified that interacts with the T. brucei serine-arginine (SR) protein termed TSR1. TSR1IP shows homology to U1 70 kDa proteins, and contains an SR rich domain as well as an acidic/arginine domain homologous to the U1 70 kDa poly(A) polymerase inhibiting domain. This protein is localized in the nucleoplasm and excluded from the nucleolus in trypanosomal bloodstream and procyclic forms. Based on structural modelling predictions and on the identification of a RNA recognition motif (RRM), it was possible to demonstrate by the yeast three-hybrid system that TSR1IP interacts with the 5' splice region of the SL RNA. All the above characteristics suggest that TSR1IP could be involved in trans-splicing.
Ismaïli
N
N
Laboratoire de Parasitologie Moléculaire, IBMM-ULB, Gosselies, Belgium.
Pérez-Morga
D
D
Walsh
P
P
Cadogan
M
M
Pays
A
A
Tebabi
P
P
Pays
E
E
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002467:Cell Nucleus / Q000378:metabolism; D016054:DNA, Protozoan / Q000235:genetics; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D012326:RNA Splicing; D016053:RNA, Protozoan / Q000235:genetics / Q000378:metabolism; D020038:RNA, Spliced Leader / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D017412:Ribonucleoprotein, U1 Small Nuclear / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017385:Sequence Homology; D017381:Spliceosomes / Q000378:metabolism; D014346:Trypanosoma brucei brucei / Q000235:genetics / Q000378:metabolism*
D016054:DNA, Protozoan; D015800:Protozoan Proteins; D016053:RNA, Protozoan; D020038:RNA, Spliced Leader; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D017412:Ribonucleoprotein, U1 Small Nuclear; C096167:SNP1 protein, S cerevisiae; C490688:SNRNP70 protein, human; D029701:Saccharomyces cerevisiae Proteins; C401867:TSR1 protein, trypanosoma