Conservation and heterogeneity of the glutamate-rich protein (GLURP) among field isolates and laboratory lines of Plasmodium faliparum

Genetic variation of the glutamate-rich protein (GLURP) of Plasmodium falciparum was analysed in 29 field isolates and 15 laboratory lines of diverse geographical origin, by DNA sequencing of the non-repetitive 5'-region (RO) of the:glurp gene. Polymorphism with respect to the length of the GLURP R2 repeat region was also analysed by a polymerase chain reaction method. As reference, the nucleotide sequence of the highly polymorphic 3'-region of the circumsporozoite protein gene was determined in the same isolates. It was found that even in the presence of variations in the GLURP R2 repeat region, immunodominant parts of the GLURP RO region are surprisingly well conserved and the conservation is most pronounced in isolates from locations with very high malaria transmission. This might indicate that the RO structure plays an important role in the parasite. (C) 2000 Elsevier Science B.V. All rights reserved.