High impact information on Rbp1

• Consistent with a role in mRNA metabolism, indirect immunofluorescence reveals that the RBP1 protein colocalizes with RNA polymerase II on larval salivary gland polytene chromosomes [1].
• We show that genes Rbp1 and Rbp1-like, which encode Drosophila homologs of mammalian SRp20, negatively autoregulate and crossregulate at the level of alternative 3' splice site selection [2].
• We show that RBP1 target sequences within the dsx repeat region are required for the efficient splicing of dsx pre-mRNA [3].
• Furthermore, using a two-hybrid system, we show protein-protein interactions between RBP1 and itself and between RBP1 and TRA-2 [4].
• The SR domain and the Gly residues within the Gly-rich domain of RBP1 were found to be involved in these protein-protein interactions [4].

Biological context of Rbp1

• The doublesex Splicing Enhancer Components Tra2 and Rbp1 Also Repress Splicing through an Intronic Silencer [5].
• The ISS also contains a consensus binding site for Rbp1, and this protein was found to facilitate repression of M1 splicing both in vitro and in Drosophila larvae [5].
• Several copies of these RBP1 target sequences were found within two regions of the dsx pre-mRNA which are important for the regulation of dsx alternative splicing, the repeat region and the purine-rich polypyrimidine tract of the regulated female-specific 3' splice site [3].
• Using a tissue culture transfection assay, we demonstrate that the Gly residues within the Gly-rich domain, the ribonucleoprotein motifs within the RNA recognition motif RNA binding domain, and the SR domain are required for regulation of dsx splicing by RBP1 in vivo [4].

Associations of Rbp1 with chemical compounds

• Moreover, our studies reveal that RBP1 contributes to the activation of female-specific dsx splicing in vivo by recognizing the RBP1 target sequences within the purine-rich polypyrimidine tract of the female-specific 3' splice site [3].
• RBP1 belongs to the Ser-Arg-rich (SR) protein family of splicing factors, which have in common a N-terminal RNA recognition motif-type RNA binding domain, a Gly-rich region, and a C-terminal SR domain [4].

Other interactions of Rbp1

• In contrast to the cooperative binding of SR proteins observed on the doublesex splicing enhancer, we found that Rbp1 and Tra2 bind to the ISS independently through distinct sequences [5].
• Cloning and sequencing of 124 PCR products revealed 12 different RRM sequences (RRM1 to RRM12) [6].
• Finally, we show that mutations in RRM1, RRM2, or the RTZF do not affect the circadian regulation of eclosion, and we discuss possible interpretations of these results [7].

References