Early expression of a Trypanosoma brucei VSG gene duplicated from an incomplete basic copy.

Intrachromosomal variant surface glycoprotein (VSG) genes in Trypanosoma brucei are expressed by a mechanism involving gene conversion. The 3' boundary of gene conversion is usually within the last 130 bp of the VSG gene, a region of partially conserved sequences. We report here the loss of the predominant telomeric A VSG gene in the cloned variant antigenic type (VAT) 5A3, leaving only an intrachromosomal A VSG gene (the A-B gene).

LRV1 viral particles in Leishmania guyanensis contain double-stranded or single-stranded RNA.

The 32-nm-diameter spherical viral particles found in the cytoplasm of Leishmania guyanensis CUMC1-1A sediment at 130S and have a buoyant density of approximately 1.4 g/ml in cesium chloride gradients. These particles contain a 5.

A retroposon in the 5' flank of a Trypanosoma brucei VSG gene lacks insertional terminal repeats.

A retroposon-like repeated sequence, ingi, occurs in high copy number in the genome of Trypanosoma brucei brucei. An ingi is present in the 5' flank of the 5C gene, an intrachromosomal IsTat 1.5 variant surface glycoprotein (VSG) gene family member.

Transcripts from the co-transposed segment of variant surface glycoprotein genes are in Trypanosoma brucei polyribosomes.

In Trypanosoma brucei the 5' proximal flanking sequences of a variant surface glycoprotein (VSG) gene, the co-transposed segment, are transcribed in a variant antigenic type- and stage-specific fashion along with the VSG gene. The precursor transcripts are subsequently processed to yield smaller transcripts from the co-transposed segment as well as the VSG mRNA. These co-transposed segment transcripts are quite abundant, polyadenylated and contain the spliced leader sequence, all characteristics of trypanosome mRNAs.

Trypanosoma brucei: frequent loss of a telomeric variant surface glycoprotein gene.

We have observed the loss of an inactive telomeric variant surface glycoprotein (VSG) gene that is located on a minichromosome in Trypanosoma brucei. If this is due to gene conversion, it is the third "silent" gene conversion (i.e.