Mutant/mutation
The mutant  expresses a C-terminal mCherry-tagged version of NAB2. The mCherry tag was introduced at the C-terminus of endogenous NAB2. Nab2::mCherry expression was controlled by the endogenous nab2 native promoters.

Protein (function)
Nuclear poly(A) binding protein 2 (NAB2), THO complex subunit 4 (THO4), nucleolar protein 3 (NPL3), G-strand binding protein 2 (GBP2) and serine/arginine-rich splicing factor 1 (SR1) are involved in nuclear mRNA export in malaria parasites.

NAB2 contains an N-terminal PWI domain and a C-terminal CCCH-type zinc finger motif, similar to yeast NAB2. Moreover, a nuclear localization signal (NLS), RX2–5PY NLS (PY-NLS), is present in NAB2

Phenotype
To examine the cellular localization of NAB2, we performed live-cell fluorescence imaging of cultured NAB2::mCherry schizonts and infected erythrocytes obtained from mice at 6 h (ring form), 12 h (trophozoite) and 18 h (late trophozoite) post-inoculation with NAB::mCherry schizonts. 
In NAB2::mCherry parasites, a single fluorescent spot representing the mCherry signal was present at the nuclear periphery in cultured schizonts and schizont-infected erythrocytes collected at 6 h (ring form) post-inoculation. At 12 h (trophozoite) and 18 h (late trophozoite) post-inoculation, speckled mCherry signals were present at the nuclear periphery in NAB2::mCherry cells. A spot of mCherry fluorescence was also detected in the cytoplasm of NAB2::mCherry parasites at 18 h (late trophozoite) post-inoculation..  

Additional information
To determine whether NAB2 localizes to the inside of the nuclear membrane in malaria parasites, we generated a NAB2::mCherry strain expressing NUP205 (nucleopore protein) fused to green fluorescent protein (GFP). Because NUP205 fluorescence increases with the size of the nucleus in P. berghei, we analyzed parasites during the late trophozoite stage (18 h post-inoculation). Live-cell fluorescence imaging revealed that the GFP signal was localized mainly to the nuclear periphery in P. berghei ANKA trophozoites, implying that NAB2 localized to the inner nuclear membrane in P. berghei  ANKA. To investigate whether the fluorescent signal of mCherry detected in the cytoplasm represented localization to mitochondria, NAB2::mCherry parasites were stained with mitotracker; the mCherry signal did not overlap that of mitochondria.

To investigate which proteins interact with NAB2, we performed protein IP using anti-mCherry beads and identified the proteins bound to NAB2 by MS. 
To identify RNAs bound by NAB2 ,we performed RIPseq on mature schizonts- and gametocytes-lysates using anti-mCherry beads and sequenced the RNAs bound to NAB2. No SR1-binding mRNAs  were detected by RIPseq of NAB2. Moreover, no SR1 homologues were detected by IP-MS of NAB2. No nuclear pore complex proteins or  export receptor-like proteins were detected by IP-MS of NAB2::mCherry. 

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