TY - JOUR
T1 - Functional Equivalence of Structurally Distinct Ribosomes in the Malaria Parasite, Plasmodium berghei
AU - Van Spaendonk, Rosalina M.L.
AU - Ramesar, Jai
AU - Van Wigcheren, Auke
AU - Eling, Wijnand
AU - Beetsma, Annette L.
AU - Van Gemert, Geert Jan
AU - Hooghof, Jo
AU - Janse, Chris J.
AU - Waters, Andrew P.
PY - 2001/6/22
Y1 - 2001/6/22
N2 - Unlike most eukaryotes, many apicomplexan parasites contain only a few unlinked copies of ribosomal RNA (rRNA) genes. Based on stage-specific expression of these genes and structural differences among the rRNA molecules it has been suggested that Plasmodium spp. produce functionally different ribosomes in different developmental stages. This hypothesis was investigated through comparison of the structure of the large subunit rRNA molecules of the rodent malaria parasite, Plasmodium berghei, and by disruption of both of the rRNA gene units that are transcribed exclusively during development of this parasite in the mosquito (S-type rRNA gene units). In contrast to the human parasite, Plasmodium falciparum, we did not find evidence of structural differences in core regions of the distinct large subunit rRNAs which are known to be associated with catalytic activity including the GTPase site that varies in P. falciparum. Knockout P. berghei parasites lacking either of the S-type gene units were able to complete development in both the vertebrate and mosquito hosts. These results formally exclude the hypothesis that two functionally different ribosome types distinct from the predominantly blood stage-expressed A-type ribosomes, are required for development of all Plasmodium species in the mosquito. The maintenance of two functionally equivalent rRNA genes might now be explained as a gene dosage phenomenon.
AB - Unlike most eukaryotes, many apicomplexan parasites contain only a few unlinked copies of ribosomal RNA (rRNA) genes. Based on stage-specific expression of these genes and structural differences among the rRNA molecules it has been suggested that Plasmodium spp. produce functionally different ribosomes in different developmental stages. This hypothesis was investigated through comparison of the structure of the large subunit rRNA molecules of the rodent malaria parasite, Plasmodium berghei, and by disruption of both of the rRNA gene units that are transcribed exclusively during development of this parasite in the mosquito (S-type rRNA gene units). In contrast to the human parasite, Plasmodium falciparum, we did not find evidence of structural differences in core regions of the distinct large subunit rRNAs which are known to be associated with catalytic activity including the GTPase site that varies in P. falciparum. Knockout P. berghei parasites lacking either of the S-type gene units were able to complete development in both the vertebrate and mosquito hosts. These results formally exclude the hypothesis that two functionally different ribosome types distinct from the predominantly blood stage-expressed A-type ribosomes, are required for development of all Plasmodium species in the mosquito. The maintenance of two functionally equivalent rRNA genes might now be explained as a gene dosage phenomenon.
UR - http://www.scopus.com/inward/record.url?scp=0035933790&partnerID=8YFLogxK
U2 - https://doi.org/10.1074/jbc.M101234200
DO - https://doi.org/10.1074/jbc.M101234200
M3 - Article
C2 - 11292830
SN - 0021-9258
VL - 276
SP - 22638
EP - 22647
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 25
ER -