Biology subjects

Dougherty, G. W.

Publications and source records attributed to Dougherty, G. W..

3 recordsLinked to original sources

bioRxiv2025

SPEF1 mediates assembly of the central pair microtubule complexes in cilia of Tetrahymena.

SPEF1 is a conserved protein that reinforces the seam of central microtubules within the distal segment of motile cilia. We show that in Tetrahymena, loss of SPEF1 destabilized the central pair throughout the cilium length, producing gaps in the microtubule lattice, loss of proximal microtubule portions, and loss of lateral projections. While both central microtubules were affected, C1 suffered more damage than C2 and the defects were already apparent during ciliary assembly. Tetrahymena cells lacking SPEF1 had fewer cilia, which contained an excessively dense ciliary matrix and abnormal densities on the doublet microtubules. Although SPEF1 loss visibly affected only the central microtubules, it localized to all stable microtubules in the cell, both ciliary and non-ciliary. Within cilia, SPEF1 was enriched near the distal tip, but was also present throughout the middle segment, where it was more concentrated along the central than the outer doublet microtubules. In live cilia, SPEF1 particles were mostly stationary and turned over slowly, some diffused but none moved by IFT. We propose that SPEF1 acts as a stabilizer of central microtubules in both the middle and distal segment and its activity contributes to central microtubule assembly.

cell biology↗

bioRxiv2017

Mutations in C11ORF70 cause primary ciliary dyskinesia with randomization of left/right body asymmetry due to outer and inner dynein arm defects

Primary ciliary dyskinesia (PCD) is characterized by chronic airway disease, male infertility and randomization of the left/right body axis caused by defects of motile cilia and sperm flagella. We identified loss-of-function mutations in the open reading frame C11ORF70 in PCD individuals from five distinct families. Transmission electron microscopy analyses and high resolution immunofluorescence microscopy demonstrate that loss-of-function mutations in C11ORF70 cause immotility of respiratory cilia and sperm flagella, respectively, due to loss of axonemal outer (ODAs) and inner dynein arms (IDAs), indicating that C11ORF70 is involved in cytoplasmic assembly of dynein arms. Expression analyses of C11ORF70 showed that C11ORF70 is expressed in ciliated respiratory cells and that the expression of C11ORF70 is upregulated during ciliogenesis, similar to other previously described cytoplasmic dynein arm assembly factors. Furthermore, C11ORF70 shows an interaction with cytoplasmic ODA/IDA assembly factor DNAAF2, supporting our hypothesis that C11ORF70 is a novel preassembly factor involved in the pathogenesis of PCD. The identification of a novel genetic defect that causes PCD and male infertility is of great clinical importance as well as for genetic counselling.

molecular biology↗

bioRxiv2017

CiliaCarta: An Integrated And Validated Compendium Of Ciliary Genes

The cilium is an essential organelle at the surface of most mammalian cells whose dysfunction causes a wide range of genetic diseases collectively called ciliopathies. The current rate at which new ciliopathy genes are identified suggests that many ciliary components remain undiscovered. We generated and rigorously analyzed genomic, proteomic, transcriptomic and evolutionary data and systematically integrated these using Bayesian statistics into a predictive score for ciliary function. This resulted in 285 candidate ciliary genes. We found experimental evidence of ciliary associations for 24 out of 36 analyzed candidate proteins. In addition, we show that OSCP1, which has previously been implicated in two distinct non-ciliary functions, causes a cilium dysfunction phenotype when depleted in zebrafish. The candidate list forms the basis of CiliaCarta, a comprehensive ciliary compendium covering 836 genes. The resource can be used to objectively prioritize candidate genes in whole exome or genome sequencing of ciliopathy patients and can be accessed at http://bioinformatics.bio.uu.nl/john/syscilia/ciliacarta/.

bioinformatics↗