Mutant/mutation
The mutant  expresses a C-terminal mCherry-tagged version of GBP2. The mCherry tag was introduced at the C-terminus of endogenous GBP2. Gbp2::mCherry expression was controlled by the endogenous gbp2 native promoters.

Protein (function)
G-strand binding protein 2 (GBP2) is a Ser/Arg-rich (SR) protein involved in mRNA surveillance and nuclear mRNA quality control in yeast. PfGBP2 (PF3D7_1006800) has homology to yeast GBP2 and is highly expressed during the blood stages of malaria parasites. GBP2 of Plasmodium spp. contains two RNA recognition motif (RRM) domains (RRM1 and RRM2) and is conserved among eukaryotes. RRM1 and RRM2 of yeast GBP2 recognize RNA. RRM2 of yeast GBP2 contains a WQxLKD motif, which is directly involved in RNA recognition. Plasmodium RRM2 contains a WKELKD motif, which is similar to the WQxLKD motif. In contrast, RRM3 (the C-terminal RRM domain of yeast) was absent in Plasmodium spp.

Phenotype
A mutant lacking expression of GBP2 (RMgm-4707) showed a (strongly) reduced production of male and female gametocytes.

To examine the cellular localization of GBP2, we performed live-cell fluorescence imaging of cultured GBP2::mCherry schizonts and infected erythrocytes obtained from mice at 6 h (ring form), 12 h (trophozoite) and 18 h (late trophozoite) post-inoculation with GBP2::mCherry schizonts The mCherry signal was distributed throughout GBP2::mCherry parasite cells at all development stages. GBP2 localized to both the nucleus and cytoplasm of malaria parasites.  

Additional information
To investigate which proteins interact with GBP2, we performed protein IP using anti-mCherry beads and identified the proteins bound to GBP2 by MS. The results of IP-MS  of GBP2::mCherry imply that GBP2 interacts with ALBA4, DOZI and CITH. DOZI and CITH are required for zygote development but not for gametocytogenesis.
To identify RNAs bound by GBP2 ,we performed RIPseq on mature schizonts- and gametocytes-lysates using antimCherry beads and sequenced the RNAs bound to GBP2 Our RIP-seq results revealed that GBP2 bound to mRNAs encoding proteins that are essential for asexual development; however, the parasitemia course was comparable in mice infected with Dgbp2 versus control parasites. These findings imply that a factor other than GBP2 is involved in the export of these mRNAs.

Other mutants