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Trypanosoma cruzi glycosomal glyceraldehyde-3-phosphate dehydrogenase does not conform to the 'hotspot' topogenic signal model.

ABSTRACT: The genes which encode glycosomal glyceraldehyde-phosphate dehydrogenase (gGAPDH) of Trypanosoma cruzi are arranged as a tandemly repeated pair on a single chromosome and are identical at the level of nucleotide sequence. They are separated by an intergenic region which contains a 317 base pair sequence with the properties of a retroposon. The genes express a 1.5 kb mRNA and a 38 kd protein. The amino acid sequence contains features characteristic of glycosomal enzymes such as peptide insertions and a C-terminal extension. However, T. cruzi gGAPDH lacks one of the positively charged 'hotspot' motifs which have been proposed as topogenic signals for import into the glycosome, a unique microbody-like organelle. Molecular modelling of the T. cruzi and T. brucei enzymes suggests that neither structure would fulfil the requirements of the 'hotspot' glycosomal import model.

SUBMITTER: Kendall G

PROVIDER: S-EPMC551983 | biostudies-other | 1990 Sep

REPOSITORIES: biostudies-other

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Trypanosoma cruzi glycosomal glyceraldehyde-3-phosphate dehydrogenase does not conform to the 'hotspot' topogenic signal model.

Kendall G G Wilderspin A F AF Ashall F F Miles M A MA Kelly J M JM

The EMBO journal 19900901 9

The genes which encode glycosomal glyceraldehyde-phosphate dehydrogenase (gGAPDH) of Trypanosoma cruzi are arranged as a tandemly repeated pair on a single chromosome and are identical at the level of nucleotide sequence. They are separated by an intergenic region which contains a 317 base pair sequence with the properties of a retroposon. The genes express a 1.5 kb mRNA and a 38 kd protein. The amino acid sequence contains features characteristic of glycosomal enzymes such as peptide insertions ...[more]

PMID: 2167831

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