The major component of the paraflagellar rod of Trypanosoma brucei is a helical protein that is encoded by two identical, tandemly linked genes

• Published in: The Journal of cell biology 1989-10, Vol.109 (4), p.1695-1709
• Main Authors: Schlaeppi, K. (Institut fur Allgemeine Mikrobiologie, Bern, Switzerland), Deflorin, J, Seebeck, T
• Format: Article
• Language: English
• Subjects: amino acid composition; Amino Acid Sequence; Amino acids; Animals; Antibodies; Base Sequence; Biological and medical sciences; Blotting, Southern; Cells; DNA; DNA - genetics; Flagella; Flagella - ultrastructure; FLAGELLUM; Fundamental and applied biological sciences. Psychology; Gels; GENE; Gene expression; Generally accepted auditing standards; GENES; Genetic Linkage; Genetic loci; Genomic Library; Genomics; helix; Messenger RNA; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Nucleic Acid Hybridization; NUCLEOTIDE; nucleotide sequence; NUCLEOTIDES; NUCLEOTIDOS; Oligonucleotide Probes; PFR protein; PROTEINAS; PROTEINE; PROTEINS; Protozoan Proteins - genetics; Protozoan Proteins - isolation & purification; Restriction Mapping; Sequence Homology, Nucleic Acid; TRYPANOSOMA; Trypanosoma brucei brucei - genetics; Trypanosoma brucei brucei - ultrastructure
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.109.4.1695

The flagellum of the parasitic hemoflagellate Trypanosoma brucei contains two major structures: (a) the microtubule axoneme, and (b) a highly ordered, filamentous array, the paraflagellar rod (PFR). This is a complex, three-dimensional structure, of yet unknown function, that extends along most of the axoneme and is closely linked to it. Its major structural component is a single protein of 600 amino acids. This PFR protein can assume two different conformations, resulting in two distinct bands of apparent molecular masses of 73 and 69 kD in SDS-gel electrophoresis. Secondary structure predictions indicate a very high helix content. Despite its biochemical similarity to the intermediate filament proteins (solubility properties, amino acid composition, and high degree of helicity), the PFR protein does not belong in this class of cytoskeletal proteins. The PFR protein is coded for by two tandemly linked genes of identical nucleotide sequence. Both genes are transcribed into stable mRNAs of very similar length that carry the mini-exon sequence at their 5′ termini.