LAX28 is required for the stable assembly of the inner dynein arm f complex, and the tether and tether head complex in Leishmania flagella

Beneke, T., Banecki, K., Fochler, S. and Gluenz, E. (2020) LAX28 is required for the stable assembly of the inner dynein arm f complex, and the tether and tether head complex in Leishmania flagella. Journal of Cell Science, 133(2), jcs239855. (doi: 10.1242/jcs.239855) (PMID:31932510)

Abstract

Motile eukaryotic flagella beat through coordinated activity of dynein motor proteins; however, the mechanisms of dynein coordination and regulation are incompletely understood. The inner dynein arm (IDA) f complex (also known as the I1 complex), and the tether and tether head (T/TH) complex are thought to be key regulators of dynein action but, unlike the IDA f complex, T/TH proteins remain poorly characterised. Here, we characterised T/TH-associated proteins in the protist Leishmania mexicana. Proteome analysis of axonemes from null mutants for the CFAP44 T/TH protein showed that they lacked the IDA f protein IC140 and a novel 28-kDa axonemal protein, LAX28. Sequence analysis identified similarities between LAX28 and the uncharacterised human sperm tail protein TEX47, both sharing features with sensory BLUF-domain-containing proteins. Leishmania lacking LAX28, CFAP44 or IC140 retained some motility, albeit with reduced swimming speed and directionality and a propensity for flagellar curling. Expression of tagged proteins in different null mutant backgrounds showed that the axonemal localisation of LAX28 requires CFAP44 and IC140, and the axonemal localisations of CFAP44 and IC140 both depend on LAX28. These data demonstrate a role for LAX28 in motility and show mutual dependencies of IDA f and T/TH-associated proteins for axonemal assembly in Leishmania.

• Item Type: Articles
• Additional Information: E.G. was supported by a Royal Society University Research Fellowship (UF100435 and UF160661). This work was supported by PhD studentships to T.B. (Medical Research Council reference 15/16_MSD_836338) and S.F. (Royal Society reference RGF\EA\180189), and Wellcome Trust grant 104627/Z/14/Z to Keith Gull (University of Oxford, UK).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Gluenz, Dr Eva
• Authors: Beneke, T., Banecki, K., Fochler, S., and Gluenz, E.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Journal of Cell Science
• Publisher: Company of Biologists
• ISSN: 0021-9533
• ISSN (Online): 1477-9137
• Published Online: 23 January 2020
• Copyright Holders: Copyright © 2020. Published by The Company of Biologists Ltd
• First Published: First published in Journal of Cell Science 133(2):jcs239855
• Publisher Policy: Reproduced in accordance with the publisher copyright policy