Biology subjects

Jana, S. C.

Publications and source records attributed to Jana, S. C..

5 recordsLinked to original sources

bioRxiv2026

Cfap410a and Cby work together with tissue-specific requirements to build Drosophila ciliary transition zones

Cilia and flagella perform essential physiological functions in eukaryotes, and defects in these organelles cause several human diseases, including cancer and ciliopathies. The architecture of cilia is highly organized. The ciliary compartment is separated from the cytoplasm by the transition zone (TZ). The severity of ciliopathies linked to TZ assembly defects highlights the TZ's critical role. Although several core conserved complexes are involved in TZ assembly, variations in TZ composition are associated with structurally and functionally diverse cilia. Here, we identify Cfap410a as a novel component of the ciliary TZ in the two Drosophila ciliated tissues, male germ cells and sensory neurons. Cfap410a is one of the two Drosophila paralogs (Cfap410a and Cfap410b) of human CFAP410, whose mutations are associated with axial spondylo-metaphyseal dysplasia, retinitis pigmentosa and amyotrophic lateral sclerosis. We show here that Cfap410a is a proximity partner of Cby and that they act cooperatively in the hierarchy of the TZ assembly program by bridging the CEP290 and MKS transition zone modules. Simultaneous loss of Cfap410a and Cby halts ciliary growth by disrupting TZ formation in multiple types of Drosophila ciliated cells, each of which exhibiting varying dependence on these two proteins. Interestingly, the function of Cfap410a and Cfap410b are not functionally redundant, indicating that the two proteins have evolved towards specific functions. In summary, our results propose a novel role for CFAP410a at the TZ and provide an explanation for how deregulation of conserved TZ components could lead to tissue-specific ciliopathies.

cell biology↗

bioRxiv2026

Centrosome maintains the integrity of and repairs mature olfactory cilia in adult Drosophila

Mechanisms of cilium assembly are well studied; however, how mature metazoan cilia maintain their structures and functions in vivo remains unknown. It is also unclear whether the centrosome-derived basal body (BB) directly contributes to ciliary homeostasis. We combined biochemistry, genetics, high-resolution subcellular imaging, and electrophysiology to investigate long-lived ciliated olfactory sensory neurons (OSNs) and their olfactory behaviour in adult Drosophila. Several centrosome assembly proteins are absent, but another subset persists through dynamic protein exchange at the BBs of mature olfactory cilia. At this ciliary base, pericentriolar material (PCM) components, e.g., {gamma}-Tubulin23C, centrosomin, and pericentrin-like protein form an interconnected network required for ciliary maintenance. Adult- and OSN-specific depletions of these proteins, particularly in combination, disrupt accumulation of the heterotrimeric kinesin-2 at the ciliary base and, subsequently, in the shaft, causing loss of ciliary tubulin, EB1, and odorant receptor co-receptor. These dysregulations cause profound loss of ciliary shaft and impair olfactory function/behaviour. The centrosomal kinases PLK1/POLO and Aurora A also work with this PCM network and are required for mature ciliary homeostasis. Remarkably, these defects in ciliary structure, function, and adult olfactory behaviour are reversible, suggesting that this centrosome-derived BB is a dynamic homeostatic epicentre that regulates trafficking and ciliary structural and compositional integrity in vivo. These findings uncover an active, centrosome-dependent, cell-autonomous mechanism for maintaining and repairing mature metazoan cilia in fully grown organs in adulthood and also provide a possible explanation for how deregulation of conserved ciliary base components could lead to progressive, late-onset cilia-related disorders.

cell biology↗

bioRxiv2020

IFT88 transports Gucy2d, a guanylyl cyclase, to maintain sensory cilia function in Drosophila

Cilia are involved in a plethora of motility and sensory-related functions. Ciliary defects cause several ciliopathies, some of which with late-onset, suggesting cilia are actively maintained. While much is known about cilia assembly, little is understood about the mechanisms of their maintenance. Given that intraflagellar transport (IFT) is essential for cilium assembly, we investigated the role of one of its main players, IFT88, in ciliary maintenance. We show that DmIFT88, the Drosophila melanogaster orthologue of IFT88, continues to move along fully formed sensory cilia, and that its acute knockdown in the ciliated neurons of the adult affects sensory behaviour. We further identify DmGucy2d, the Drosophila guanylyl cyclase 2d, as a DmIFT88 cargo, whose loss also leads to defects in sensory behaviour maintenance. DmIFT88 binds to the intracellular part of DmGucy2d, which is evolutionarily conserved and mutated in several degenerative retina diseases, taking the cyclase into the cilia. Our results offer a novel mechanism for the maintenance of sensory cilia function and its potential role in human diseases.

cell biology↗

bioRxiv2020

Heterotrimeric kinesin-2 motor subunit, KLP68D, localises Drosophila odour receptor coreceptor in the distal domain of the olfactory cilia

Ciliary localisation of the odour receptor coreceptor (Orco) is essential for insect olfaction. Here, we show that in the Drosophila antenna Orco enters the bipartite cilia expressed on the olfactory sensory neurons in two discrete, one-hour intervals after the adult eclosion. Genetic analyses suggest that the heterotrimeric kinesin-2 is essential for Orco transfer from the base into the cilium. Using in vitro pulldown assay, we show that Orco binds to the C-terminal tail domain of KLP68D, the {beta}-subunit of kinesin-2. Reduced Orco enrichment decreases electrophysiological response to odours and loss of olfactory behaviour. Finally, we show that kinesin-2 function is necessary to compact Orco to an approximately four-micron stretch at the distal portion of the ciliary outer-segment bearing singlet microtubule filaments. Altogether, these results highlight an independent, tissue-specific regulation of Orco entry at specific developmental stages and its localisation to a ciliary subdomain by kinesin-2. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/395905v1_ufig1.gif" ALT="Figure 1"> View larger version (69K): org.highwire.dtl.DTLVardef@177d376org.highwire.dtl.DTLVardef@1dc14d6org.highwire.dtl.DTLVardef@1dc2d21org.highwire.dtl.DTLVardef@16e90c_HPS_FORMAT_FIGEXP M_FIG C_FIG Author SummaryJana, Jain, Dutta et al., show that the odour receptor coreceptor only enters the cilia expressed on olfactory sensory neurons at specified developmental stages requiring heterotrimeric kinesin-2. The motor also helps to localise the coreceptor in a compact, environment-exposed domain at the ciliary outer-segment. HighlightsO_LIOdorant receptor coreceptor (Orco) selectively enters the olfactory cilia. C_LIO_LIOrco localises in a specific domain at the distal segment of the olfactory cilium. C_LIO_LIOrco/ORx binds to the C-terminal tail domain of the kinesin-2{beta} motor subunit. C_LIO_LIOrco entry across the transition zone and its positioning require Kinesin-2. C_LI

cell biology↗

bioRxiv2018

An ancestral role of pericentrin in centriole formation through SAS-6 recruitment

The centrosome is composed of two centrioles surrounded by a microtubule-nucleating pericentriolar matrix (PCM). Centrioles regulate matrix assembly. Here we ask whether the matrix also regulates centriole assembly. To define the interaction between the matrix and individual centriole components, we take advantage of a heterologous expression system using fission yeast. Importantly, its centrosome, the spindle pole body (SPB), has matrix but no centrioles. Surprisingly, we observed that the SPB can recruit several animal centriole components. Pcp1/pericentrin, a conserved matrix component that is often upregulated in cancer, recruits a critical centriole constituent, SAS-6. We further show that this novel interaction is conserved and important for centriole biogenesis and elongation in animals. We speculate that the Pcp1/pericentrin-SAS-6 interaction surface was conserved for one billion years of evolution after centriole loss in yeasts, due to its conserved binding to calmodulin. This study reveals an ancestral relationship between pericentrin and the centriole, where both regulate each other assembly, ensuring mutual localisation.\n\nShort summaryThe pericentriolar matrix (PCM) is not only important for microtubule-nucleation but also can regulate centriole biogenesis. Ito et al. reveal an ancestral interaction between the centriole protein SAS-6 and the PCM component pericentrin, which regulates centriole biogenesis and elongation.

cell biology↗