Mutant/mutation
The mutant lacks expression of P230p.

Protein (function)
The P230p protein is a member of a small family of proteins, the 6-cysteine (cys) family of (surface) proteins. The proteins are characterized by domains of roughly 120 amino acids in size that contain six positionally conserved cysteines (6-cys). Although some species of Plasmodium (may) contain unique members of the 6-cys family, ten members have been identified that are conserved both in structure as well as in genome organization throughout the genus. Some of the conserved 6-cys proteins are encoded by genes that form paralogous gene-pairs which are closely linked in the genome separated by less then 2 kb of intergenic region. Most members have a GPI anchor and are predicted membrane surface proteins whereas others appear to be secreted and most members are expressed in a discrete stage-specific manner in gametocytes, sporozoites or merozoites (see also 'Additional Information'). Evidence has been presented that P230p is specifically expressed in gametocytes of P. berghei.

Phenotype
Phenotype analyses indicate that that P230p is not essential in the complete life cycle of the parasite. The mutant lacking P230p shows growth and development characteristics that are comparable to wild type parasites both in the vertebrate host and in the mosquito.

Additional information
The p230p gene forms a paralogous gene pair with the gene p230 (PB000403.00.0; PFB0405w), which are closely linked in the genome. In contrast to the non-essential role of P230p, the paralog P230 plays an important role in male fertility and fertilisation (see mutant RMgm-350 which lacks expression of P230).

The p230p locus is commonly used as a locus for integration of transgenes in P. berghei, for example fluorescent proteins.

The mutant described here, Δp230p-I, contains a partial disrupted p230p gene. A fragment of the gene is deleted from the second 6-cys domain (i.e. the first 894 amino acids are still present in the genome). A second mutant (Δp230p-II; RMgm-352) has been generated and the deleted fragment includes part of the first 6-cys domain (i.e. the first 492 amino acids are still present).

Table: P. falciparum gene members of the 6-cys family

 
Other mutants
RMgm-350: A mutant lacking expression of the paralog P230 (PB000403.00.0; PFB0405w)
RMgm-352: An independent mutant lacking expression of P230p