| Successful modification | The parasite was generated by the genetic modification |
| The mutant contains the following genetic modification(s) |
Gene disruption
|
| Reference (PubMed-PMID number) |
Reference 1 (PMID number) : 25759501
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| MR4 number |
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| Parent parasite used to introduce the genetic modification |
| Rodent Malaria Parasite | P. yoelii |
| Parent strain/line | P. y. yoelii 17XNL |
| Name parent line/clone |
Not applicable
|
| Other information parent line | |
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| The mutant parasite was generated by |
| Name PI/Researcher | Qi Y; Xin-zhuan S |
| Name Group/Department | State Key Laboratory of Cellular Stress Biology |
| Name Institute | Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University |
| City | Xiamen, Fujian |
| Country | China |
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| Name of the mutant parasite |
| RMgm number | RMgm-1223 |
| Principal name | DssuKO1-3 |
| Alternative name | |
| Standardized name | |
| Is the mutant parasite cloned after genetic modification | Yes |
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| Phenotype |
| Asexual blood stage | Not tested |
| Gametocyte/Gamete | Not tested |
| Fertilization and ookinete | Not tested |
| Oocyst | Repeated mosquito-feeding experiments with DssuKO1 produced no oocysts; however, smaller and fewer day 9 oocysts (compared with wild-type) were found from clones of the DssuKO2 and DssuKO3 parasites. No salivary gland sporozoites were observed from DssuKO2 and DssuKO3 parasite clones, and infection of mice with day 15 (and day 20 or 23) salivary gland extracts produced no mouse infection. |
| Sporozoite | Repeated mosquito-feeding experiments with DssuKO1 produced no oocysts; however, smaller and fewer day 9 oocysts (compared with wild-type) were found from clones of the DssuKO2 and DssuKO3 parasites. No salivary gland sporozoites were observed from DssuKO2 and DssuKO3 parasite clones, and infection of mice with day 15 (and day 20 or 23) salivary gland extracts produced no mouse infection. |
| Liver stage | Not tested |
| Additional remarks phenotype | Mutant/mutation
The mutant lacks expression of the small subunit (ssu) of the d-type ribosomal rna gene unit (located on chromosome 6).
Protein (function)
P. yoelii contains four distinct copies of the ribosomal RNA gene units (A-D), each encoding the following rRNA molecules: large subunit (LSU; 28 S) rRNA, small subunit (SSU; 18 S) rRNA and 5.8 S rRNA .
Based on differences in sequence and expression the four gene units are divided into the blood stage A-type (a- and b-unit) and S-type (c- and d-units), which is transcribed mainly in the proliferative stages in the mosquito. The A-type ribosomes are present in the liver and blood stages of the parasite, and the S-type ribosomes are the predominant types produced during development in the mosquito.
Phenotype
Repeated mosquito-feeding experiments with DssuKO1 produced no oocysts; however, smaller and fewer day 9 oocysts (compared with wild-type) were found from clones of the DssuKO2 and DssuKO3 parasites. No salivary gland sporozoites were observed from DssuKO2 and DssuKO3 parasite clones, and infection of mice with day 15 (and day 20 or 23) salivary gland extracts produced no mouse infection.
These observations indicate that the (ssu) d-type rRNA gene unit is essential for the production of sporozoites.
Additional information
In P. berghei disruption of the d-type rRNA gene unit does have a relatively minor effect on parasite development, resulting in a delayed maturation of oocysts. The sporozoites formed are infectious to the mammalian host (Swiss mice). See RMgm-23, RMgm-24, RMgm-25.
Other mutants
RMgm-1224 - A mutant lacking expression of the small subunit (ssu) of the c-type ribosomal rna gene unit |
*RMgm-1223
