Mutant/mutation
The mutant lacks expression of AP2R-1

See also mutants RMgm-5199 and RMgm-5200 targeting this gene by the same group with a different expression pattern when the gene was tagged with GFP (as a result of translational repression in female gametocytes).

Protein (function)
Through a screen, a gene containing a putative AP2 domain was identified (PBANKA_0612400). Although the E- value obtained from SMART analysis was not small enough to conclude that it is an AP2 domain (E-value =0.042),  the domain has a structural characteristics of AP2 domain: three antiparallel β-sheets followed by a single α-helix.  A unique feature in this putative AP2 domain was a  long insertion sequence between predicted sheets 2 and 3.  Assuming that the high E-value is attributed to this sequence, we deleted it from the original sequence of the putative AP2 domain  and subjected the modified sequence to SMART analysis. As a result, a much smaller E-value  (E-value <1 ×10⁵) was obtained from the putative AP2 domain, suggesting that this gene, hereafter referred to as AP2 TF-related gene 1 (AP2R-1), is a novel member of the Plasmodium AP2 family.

Phenotype
Two independent disruptants were obtained. Mature-appearing female and male gametocytes were observed in Giemsa-stained blood smears. However, in ookinete culture, they failed to develop into mature ookinetes. In mosquito transmission experiments, no oocysts were found in the midgut 14 days after mosquito blood-feeding.

Additional information
Fluorescence microscopy using transgenic parasites expressing AP2R-1 as a mNeonGreen-tagged protein showed that it is expressed in the  nucleus of female gametocytes. 

From the Abstract:
'Fluorescence microscopy showed that AP2-G expression was first observed in the parasite 12 h after erythrocyte invasion and peaked at 18 h when sexual features were first manifested in  early gametocytes. Expression of  AP2-G decreased with manifestation of  sex-specific features. Chromatin immunoprecipitation followed by sequencing (ChIP-seq) was performed at peak AP2-G expression and identified over 1000 binding sites in the genome. The main binding motif of the TF predicted from the binding sites was GTACNY. Predicted targets contained a number of genes related to protein biogenesis, suggesting that AP2-G plays a role in establishing a cellular basis required for sexual differentiation. AP2-G binding sites also existed upstream of gametocyte-specific TFs, namely AP2-G2, AP2-FG, and AP2-G itself. Furthermore, the target contained two AP2 TF-related genes. Disruption of  these genes resulted in  the arrest of  ookinete development. These results suggest another role of  AP2-G: activating a  transcriptional cascade to  promote conversion into early gametocytes.'

Other mutants