Biology subjects

Kuriakose, A.

Publications and source records attributed to Kuriakose, A..

4 recordsLinked to original sources

bioRxiv2025

Mitochondrial dysfunction in Machado Joseph disease: insights from a multi-model system

Spinocerebellar ataxia type-3 (SCA3), also known as Machado Joseph disease, MJD) is a fatal, neurodegenerative disease belonging to the polyglutamine repeat disease family, caused by inheritance of an abnormal form of the ATXN3 gene, carrying a longer than usual trinucleotide repeat sequence. Within this study we explored mitochondrial function in a range of different experimental models of MJD, including transgenic zebrafish, mice and neuronal cells, to gain an understanding of mitochondrial function in the disease, and possible mechanisms of any dysfunction. Firstly, we examined the transgenic CMVMJD135 mouse model that develops impaired movement, neurodegeneration and decreased survival. We performed proteomic analysis on brain lysates extracted from a cohort of male and female WT and MJD mice, for analysis of differences in male and female mice separately. We identified that a major difference predicted by Ingenuity Pathway Analysis to be in both male and female MJD mice was related to impaired oxidative phosphorylation and mitochondrial dysfunction. We examined primary neuron cultures obtained from CMVMJD135 mice, validating the findings of the proteomic analysis, and finding changes to mitochondrial morphology, as well. We further examined a transgenic zebrafish model of MJD that expresses EGFP fused human ataxin-3 with short or long polyQ stretches (23 or 84Q, respectively) in neurons (expression driven under the elav/HuC promoter). The MJD zebrafish also exhibit altered mitochondrial electron transport chain complex protein levels, together with enhanced sensitivity to rotenone administration, which may be a valuable readout for treatment investigation studies in the future. Together, this study confirms, and extends on, the growing body of evidence suggesting that mitochondrial dysfunction plays a role in MJD, warranting investigation for therapeutic intervention.

neuroscience↗

bioRxiv2025

Gut transit and gut microbiome changes occur prior to the onset of motor impairment in a mouse model of Machado-Joseph disease

We previously identified microbial shifts prior to the onset of motor and neurological symptoms within a mouse model of the fatal neurodegenerative disease Machado-Joseph disease (MJD). Here, we aimed to explore possible mechanisms contributing to these changes within the microbiome-gut-brain axis, and whether it preceded or followed central neurodegeneration. Here, we report that pre-symptomatic male MJD mice present with significantly different microbiome communities as early as 5-weeks-old. Furthermore, we show that male MJD mice have faster total gut transit times by 9-weeks-old, prior to signs of impaired motor function by 11-weeks-old. To elucidate whether these microbial and colonic functional changes are due to the presence of pathological and morphological changes in the gut, we quantified the formation of ataxin-3 protein aggregates within the gut and examined morphological changes within the gut of pre- and early symptomatic MJD mice relative to proteinopathy in the brain. Interestingly, we observed ataxin-3 aggregates within the brains of pre-symptomatic MJD mice, with significantly more aggregates present in MJD than WT mice from 7-weeks-of-age, an earlier timepoint than previously reported, coinciding with changes within the microbiome. However, we observed no ataxin-3 protein aggregates and no changes in enteric neuron populations or morphology within the gut. Analysis of endocrine factors involved in gut motility and inflammatory markers within the small intestine of 13-week-old males revealed increased expression of genes encoding cholecystokinin (Cck), ghrelin (Ghrl), heme oxygenase (Ho1), interleukin-1 beta (Il1b), and decreased inducible nitric oxide synthase (Nos2). Together, we demonstrate for the first time that colonic dysfunction occurs after gut microbiome changes, but prior to the onset of motor impairments in male MJD mice. Our work suggests that whilst proteinopathy or morphological changes within the gut may not be involved in these changes, inflammation and related endocrine changes could have a role in the interplay between the gut and brain during MJD development, warranting further investigation.

neuroscience↗

bioRxiv2022

Identification of a novel interaction between Theileria Prohibitin (TaPHB-1) and bovine RUVBL-1

Bovine tropical theileriosis causes huge economic loss worldwide. It is a tick borne disease of bovine caused by the parasite Theileria annulata. T. annulata is an intracellular parasite that belongs to the phylum Apicomplexa. The sporozoites of T. annulata are released by the tick into the bloodstream of the host during the blood meal that invades bovine B cells, macrophages, or monocytes. This infection leads to the transformation of the host cells and brings cancer-like phenotype in the host cells. The parasite proteins play a vital role in the transformation of the host cell. However, the parasite factors involved in the host cell transformation are not well explored. Previously, TaPIN1, a peptidyl-prolyl isomerase of T. annulata, was shown to be secreted to the host cytosol and play a role in the host cell transformation. The present study was carried out to explore the parasite-host interactions that may play an important role in the host cell transformation. We identified the parasite proteins that are expressed in the schizont stage with a signal peptide. We narrow down our search to a parasite prohibitin. The in silico analysis of T. annulata prohibitin (TA04375, TaPHB-1) showed that TaPHB-1 shares homology with the mammalian prohibitin 1. With the localization experiments, we confirmed that TaPHB-1 is exported to the parasite surface and also to the host cell cytosol. Further, we observed that the localization of host prohibitin differs in the parasite-infected cells and could not be reverted back by the elimination of the parasite in the infected cells. We found through the yeast-two-hybrid studies that bovine RUVBL1 (BoRUVBL-1) interacts with TaPHB-1. The interaction between BoRUVBL1 and TaPHB-1 was predominantly observed on the parasite surface in the infected bovine cells. The interaction was further confirmed with immunoprecipitation and LC-MS/MS analysis. Further, the LC-MS/MS based TaPHB-1 interactome study reveals that it interacts with proteins that regulate actin cytoskeleton organization, protein folding, mRNA processing, and metabolic processes. Our finding suggests that the parasite releases prohibitin protein into the cytoplasm of the host cell where it interacts with the host RUVBL-1. This finding has implications not only in the understanding of Theileria parasite biology in greater depth but also in the cancer biology where previously differential localization of prohibitin proteins was observed but its interaction partner was not known. Author summaryTheileria annulata, an apicomplexan, is a unique parasite which can transform host leucocytes. This parasite uses this strategy for its own multiplication. The cells infected with this parasite, when treated with buparvaquone, an anti-theilerial drug, cannot survive without the parasite. This observation suggests that the parasite derived factors are required to maintain the cancerous phenotype of the host cell. We mined the parasite proteome to find out the proteins with signal sequence that may be secreted to the host cell cytosol and being expressed in the schizont stage. The parasite prohibitin (TaPHB-1) chosen for this study was found to be secreted to the host cytoplasm and on the parasite surface. Interestingly, we observed a noticeable change in the localization of the host prohibitin in the parasite infected cells. The host prohibitin that is normally localized to the mitochondria in the uninfected cells was observed in the host cell nucleus similar to the cancerous cells. Since the parasite protein is exported to the host cytoplasm we looked for its interacting partner. We performed yeast-two-hybrid screening with TaPHB-1 with in-house prepared the cDNA library of the infected bovine leucocytes. We identified bovine RUVBL1 as the interacting partner of TaPHB-1. Interestingly, the interaction between parasite prohibitin and bovine RUVBL1 was observed on the parasite surface. Further, analysis of the parasite prohibitin interactome in the infected cells shows that it might be involved with those proteins which regulate actin cytoskeleton organization, protein folding, mRNA processing and metabolic process. Since parasite infected cells have cancer like phenotype, the identification of this novel interaction will open up new avenues not only in the arena of parasite biology but also in the domain of cancer biology.

microbiology↗

bioRxiv2021

Notch Intracellular Domain Plasmid Delivery via Poly(lactic-co-glycolic acid)Nanoparticles to Upregulate Notch Signaling

Notch signaling is a highly conserved signaling system that is required for embryonic development and regeneration of organs. When the signal is lost, maldevelopment occurs and leads to a lethal state. Liposomes and retroviruses are most commonly used to deliver genetic material to cells. However, there are many drawbacks to these systems such as increased toxicity, nonspecific delivery, short half-life, and stability after formulation. We utilized the negatively charged and FDA approved polymer poly(lactic-co-glycolic acid) to encapsulate Notch Intracellular Domain-containing plasmid in nanoparticles. In this study, we show that primary human umbilical vein endothelial cells readily uptake the nanoparticles with and without specific antibody targets. We demonstrated that our nanoparticles also are nontoxic, stable over time, and compatible with blood. We also determined that we can successfully transfect primary human umbilical vein endothelial cells (HUVECs) with our nanoparticles in static and dynamic environments. Lastly, we elucidated that our transfection upregulates the downstream genes of Notch signaling, indicating that the payload was viable and successfully altered the genetic downstream effects.

bioengineering↗