# MECHANISMS OF ANTIGENIC VARIATION IN TRYPANOSOMES

> **NIH NIH R01** · UNIVERSITY OF IOWA · 1989 · $163,748

## Abstract

The objective of this proposal is to determine the molecular events at the
RNA and DNA level that are responsible for antigenic variation in African
trypanosomes.  Several projects are planned, most of which are extensions
of research currently in progress.  The RNA polymerase activities in
trypanosome cells are being examined.  The separation procedures that have
been used to resolve the three RNA polymerase activities in other
eukaryotes yield only one peak of RNA polymerase activity in trypanosome
extracts.  The reason for this difference will be explored by (i) further
efforts to purify this activity, (ii) examination of in vitro transcription
of purified DNA templates by trypanosome extracts and
(iii)\characterization of the gene(s) for one or more trypanosome RNA
polymerase subunits that have been identified by cross-hybridization with
heterologous gene probes.  Several additional trypanosome genes that have
specific properties of interest will be examined.  These genes include
ones that code for (i) phosphoglycerol kinase, alcohol dehydrogenase and
rRNAs, (ii) three bloodstream VSGs whose order of appearance in a serodeme
appears to be  either pre-programmed (in one case) or random (in another
case) and (iii) VSGs that are synthesized during the metacyclic state of
trypanosome development or are unique in some other way.  Another series of
experiments will investigate the distinctive features of the 5'-termini of
many, if not all, trypanosome mRNAs including the VSG mRNAs.  The possible
occurrence of 5'-CAP structures will be determined, the presence of the
35-mer on structural RNA precursors will be investigated and the potential
precursor-product relationship between the transcript of the 35-mer DNA
coding region and the 35-mer at the 5'-termini of RNAs will be
established.  It is anticipated that the results of these projects will
contribute to a better understanding of the molecular basis for antigenic
variation and facilitate the design of better methods to combat or control
the disease caused by this parasite.

## Key facts

- **NIH application ID:** 3128345
- **Project number:** 5R01AI018954-08
- **Recipient organization:** UNIVERSITY OF IOWA
- **SAM.gov UEI:** Z1H9VJS8NG16
- **Principal Investigator:** John E Donelson
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1989
- **Award amount:** $163,748
- **Award type:** 5
- **Project period:** 1982-06-01 → 1990-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3128345

## Citation

> US National Institutes of Health, RePORTER application 3128345, MECHANISMS OF ANTIGENIC VARIATION IN TRYPANOSOMES (5R01AI018954-08). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3128345. Licensed CC0.

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