1
|
Xu W, Xu M, Yin Q, Liu C, Cao Q, Deng Y, Liu S, He G. A novel homozygous TUB mutation associated with autosomal recessive retinitis pigmentosa in a consanguineous Chinese family. BMC Med Genomics 2023; 16:9. [PMID: 36650547 PMCID: PMC9847046 DOI: 10.1186/s12920-023-01430-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 01/04/2023] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Retinitis pigmentosa (RP) is the most common type of inherited retinopathy. At least 69 genes for RP have been identified. A significant proportion of RP, however, remains genetically unsolved. In this study, the genetic basis of a Chinese consanguineous family with presumed autosomal recessive retinitis pigmentosa (arRP) was investigated. METHODS Overall ophthalmic examinations, including funduscopy, decimal best-corrected visual acuity, axial length and electroretinography (ERG) were performed for the family. Genomic DNA from peripheral blood of the proband was subjected to whole exome sequencing. In silico predictions, structural modelling, and minigene assays were conducted to evaluate the pathogenicity of the variant. RESULTS A novel homozygous variant (NM_003320.4: c.1379A > G) in the TUB gene was identified as a candidate pathogenic variant in this parental consanguineous pedigree. This variant co-segregated with the disease in this pedigree and was absent in 118 ethnically matched healthy controls. It's an extremely rare variant that is neither deposited in population databases (1000 Genomes, ExAC, GnomAD, or Exome Variant Server) nor reported in the literature. Phylogenetic analysis indicated that the Asn residue at codon 460 of TUB is highly conserved across diverse species from tropicalis to humans. It was also completely conserved among the TUB, TULP1, TULP2, and TULP3 family proteins. Multiple bioinformatic algorithms predicted that this variant was deleterious. CONCLUSIONS A novel missense variant in TUB was identified, which was probably the pathogenic basis for arRP in this consanguineous family. This is the first report of a homozygous missense variant in TUB for RP.
Collapse
Affiliation(s)
- Wei Xu
- grid.477407.70000 0004 1806 9292Central Laboratory, Hunan Provincial People’s Hospital (the First Affiliated Hospital of Hunan Normal University), Changsha, 410000 China
| | - Ming Xu
- grid.464229.f0000 0004 1765 8757School of Medicine, Changsha Medical University, Changsha, 410219 China
| | - Qinqin Yin
- grid.477407.70000 0004 1806 9292Department of Ophthalmology, Hunan Provincial People’s Hospital (the First Affiliated Hospital of Hunan Normal University), Changsha, 410000 China
| | - Chuangyi Liu
- grid.477407.70000 0004 1806 9292Department of Ophthalmology, Hunan Provincial People’s Hospital (the First Affiliated Hospital of Hunan Normal University), Changsha, 410000 China
| | - Qiuxiang Cao
- grid.411427.50000 0001 0089 3695School of Life Sciences, Hunan Normal University, Changsha, 410081 China
| | - Yun Deng
- grid.411427.50000 0001 0089 3695School of Life Sciences, Hunan Normal University, Changsha, 410081 China
| | - Sulai Liu
- grid.477407.70000 0004 1806 9292Central Laboratory, Hunan Provincial People’s Hospital (the First Affiliated Hospital of Hunan Normal University), Changsha, 410000 China
| | - Guiyun He
- Department of Ophthalmology, Hunan Provincial People's Hospital (the First Affiliated Hospital of Hunan Normal University), Changsha, 410000, China.
| |
Collapse
|
2
|
Li QF, Wang H, Zheng L, Yang F, Li HZ, Li JX, Cheng D, Lu K, Liu Y. Effects of Modest Hypoxia and Exercise on Cardiac Function, Sleep-Activity, Negative Geotaxis Behavior of Aged Female Drosophila. Front Physiol 2020; 10:1610. [PMID: 32038290 PMCID: PMC6985434 DOI: 10.3389/fphys.2019.01610] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 12/23/2019] [Indexed: 12/13/2022] Open
Abstract
Mild normobaric hypoxia (NH) and modest exercise have multiple beneficial effects on health, but the changes in physiological function induced by NH and/or exercise remain unclear. The purpose of this investigation was to examine the specific effects of NH and/or exercise on cardiac function and myocardial structure and behavior including sleep-activity and negative geotaxis in aged Drosophila. We also assessed the survival rate of flies after hypoxia and/or exercise. One-thousand wild-type w1118 virgin female flies were randomly divided into four groups and treated with NH and/or exercise from ages 3-6 weeks. We found that exercise remarkably delayed the decline of actin and myosin and the age-related changes in cardiac structure, improved abnormal cardiac contraction, and enhanced the cardiac pumping force by inducing cardiac hypertrophy and delaying deterioration of cardiac contractility and diastolic compliance, and improved abnormal heart contraction. NH also increased the content of actin and myosin, but induced a decrease in heart diameter and heart rate, as well as an increase in the number of mitochondria and deeper sleep, which may be the manifestation of energy saving under long-term hypoxia. Both NH and exercise improved sleep quality and climbing ability of aged flies, as well as extended the maximum life span, which shows the benefits of hypoxia and exercise. Finally, the superposition of NH and exercise did not impart any obvious physiological and behavior improvement. Therefore, it is necessary to further explore the appropriate combination of hypoxia and exercise.
Collapse
Affiliation(s)
- Qiu Fang Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Hui Wang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Lan Zheng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Fan Yang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Han Zhe Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Jin Xiu Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Dan Cheng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Kai Lu
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Yang Liu
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| |
Collapse
|
3
|
DiTirro D, Philbrook A, Rubino K, Sengupta P. The Caenorhabditis elegans Tubby homolog dynamically modulates olfactory cilia membrane morphogenesis and phospholipid composition. eLife 2019; 8:48789. [PMID: 31259686 PMCID: PMC6624019 DOI: 10.7554/elife.48789] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 06/21/2019] [Indexed: 12/13/2022] Open
Abstract
Plasticity in sensory signaling is partly mediated via regulated trafficking of signaling molecules to and from primary cilia. Tubby-related proteins regulate ciliary protein transport; however, their roles in remodeling cilia properties are not fully understood. We find that the C. elegans TUB-1 Tubby homolog regulates membrane morphogenesis and signaling protein transport in specialized sensory cilia. In particular, TUB-1 is essential for sensory signaling-dependent reshaping of olfactory cilia morphology. We show that compromised sensory signaling alters cilia membrane phosphoinositide composition via TUB-1-dependent trafficking of a PIP5 kinase. TUB-1 regulates localization of this lipid kinase at the cilia base in part via localization of the AP-2 adaptor complex subunit DPY-23. Our results describe new functions for Tubby proteins in the dynamic regulation of cilia membrane lipid composition, morphology, and signaling protein content, and suggest that this conserved family of proteins plays a critical role in mediating cilia structural and functional plasticity.
Collapse
Affiliation(s)
- Danielle DiTirro
- Department of Biology, Brandeis University, Waltham, United States
| | - Alison Philbrook
- Department of Biology, Brandeis University, Waltham, United States
| | - Kendrick Rubino
- Department of Biology, Brandeis University, Waltham, United States
| | - Piali Sengupta
- Department of Biology, Brandeis University, Waltham, United States
| |
Collapse
|
4
|
Lehmann M, Knust E, Hebbar S. Drosophila melanogaster: A Valuable Genetic Model Organism to Elucidate the Biology of Retinitis Pigmentosa. Methods Mol Biol 2019; 1834:221-249. [PMID: 30324448 DOI: 10.1007/978-1-4939-8669-9_16] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Retinitis pigmentosa (RP) is a complex inherited disease. It is associated with mutations in a wide variety of genes with many different functions. These mutations impact the integrity of rod photoreceptors and ultimately result in the progressive degeneration of rods and cone photoreceptors in the retina, leading to complete blindness. A hallmark of this disease is the variable degree to which symptoms are manifest in patients. This is indicative of the influence of the environment, and/or of the distinct genetic makeup of the individual.The fruit fly, Drosophila melanogaster, has effectively proven to be a great model system to better understand interconnected genetic networks. Unraveling genetic interactions and thereby different cellular processes is relatively easy because more than a century of research on flies has enabled the creation of sophisticated genetic tools to perturb gene function. A remarkable conservation of disease genes across evolution and the similarity of the general organization of the fly and vertebrate photoreceptor cell had prompted research on fly retinal degeneration. To date six fly models for RP, including RP4, RP11, RP12, RP14, RP25, and RP26, have been established, and have provided useful information on RP disease biology. In this chapter, an outline of approaches and experimental specifications are described to enable utilizing or developing new fly models of RP.
Collapse
Affiliation(s)
- Malte Lehmann
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Elisabeth Knust
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
| | - Sarita Hebbar
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
| |
Collapse
|
5
|
Wang M, Xu Z, Kong Y. The tubby-like proteins kingdom in animals and plants. Gene 2018; 642:16-25. [DOI: 10.1016/j.gene.2017.10.077] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 08/15/2017] [Accepted: 10/27/2017] [Indexed: 11/28/2022]
|
6
|
Carbone MA, Yamamoto A, Huang W, Lyman RA, Meadors TB, Yamamoto R, Anholt RRH, Mackay TFC. Genetic architecture of natural variation in visual senescence in Drosophila. Proc Natl Acad Sci U S A 2016; 113:E6620-E6629. [PMID: 27791033 PMCID: PMC5087026 DOI: 10.1073/pnas.1613833113] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Senescence, i.e., functional decline with age, is a major determinant of health span in a rapidly aging population, but the genetic basis of interindividual variation in senescence remains largely unknown. Visual decline and age-related eye disorders are common manifestations of senescence, but disentangling age-dependent visual decline in human populations is challenging due to inability to control genetic background and variation in histories of environmental exposures. We assessed the genetic basis of natural variation in visual senescence by measuring age-dependent decline in phototaxis using Drosophila melanogaster as a genetic model system. We quantified phototaxis at 1, 2, and 4 wk of age in the sequenced, inbred lines of the Drosophila melanogaster Genetic Reference Panel (DGRP) and found an average decline in phototaxis with age. We observed significant genetic variation for phototaxis at each age and significant genetic variation in senescence of phototaxis that is only partly correlated with phototaxis. Genome-wide association analyses in the DGRP and a DGRP-derived outbred, advanced intercross population identified candidate genes and genetic networks associated with eye and nervous system development and function, including seven genes with human orthologs previously associated with eye diseases. Ninety percent of candidate genes were functionally validated with targeted RNAi-mediated suppression of gene expression. Absence of candidate genes previously implicated with longevity indicates physiological systems may undergo senescence independent of organismal life span. Furthermore, we show that genes that shape early developmental processes also contribute to senescence, demonstrating that senescence is part of a genetic continuum that acts throughout the life span.
Collapse
Affiliation(s)
- Mary Anna Carbone
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695; Program in Genetics, North Carolina State University, Raleigh, NC 27695
| | - Akihiko Yamamoto
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695; Program in Genetics, North Carolina State University, Raleigh, NC 27695
| | - Wen Huang
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695; Program in Genetics, North Carolina State University, Raleigh, NC 27695; Initiative in Biological Complexity, North Carolina State University, Raleigh, NC 27695
| | - Rachel A Lyman
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695
| | - Tess Brune Meadors
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695
| | - Ryoan Yamamoto
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695
| | - Robert R H Anholt
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695; Program in Genetics, North Carolina State University, Raleigh, NC 27695; Initiative in Biological Complexity, North Carolina State University, Raleigh, NC 27695
| | - Trudy F C Mackay
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695; Program in Genetics, North Carolina State University, Raleigh, NC 27695; Initiative in Biological Complexity, North Carolina State University, Raleigh, NC 27695
| |
Collapse
|
7
|
The Disease Protein Tulp1 Is Essential for Periactive Zone Endocytosis in Photoreceptor Ribbon Synapses. J Neurosci 2016; 36:2473-93. [PMID: 26911694 DOI: 10.1523/jneurosci.2275-15.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mutations in the Tulp1 gene cause severe, early-onset retinitis pigmentosa (RP14) in humans. In the retina, Tulp1 is mainly expressed in photoreceptors that use ribbon synapses to communicate with the inner retina. In the present study, we demonstrate that Tulp1 is highly enriched in the periactive zone of photoreceptor presynaptic terminals where Tulp1 colocalizes with major endocytic proteins close to the synaptic ribbon. Analyses of Tulp1 knock-out mice demonstrate that Tulp1 is essential to keep endocytic proteins enriched at the periactive zone and to maintain high levels of endocytic activity close to the synaptic ribbon. Moreover, we have discovered a novel interaction between Tulp1 and the synaptic ribbon protein RIBEYE, which is important to maintain synaptic ribbon integrity. The current findings suggest a new model for Tulp1-mediated localization of the endocytic machinery at the periactive zone of ribbon synapses and offer a new rationale and mechanism for vision loss associated with genetic defects in Tulp1.
Collapse
|
8
|
Bokolia NP, Mishra M. Hearing molecules, mechanism and transportation: modeled in Drosophila melanogaster. Dev Neurobiol 2014; 75:109-30. [PMID: 25081222 DOI: 10.1002/dneu.22221] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/29/2014] [Accepted: 07/29/2014] [Indexed: 01/19/2023]
Abstract
Mechanosensory transduction underlies the perception of touch, sound and acceleration. The mechanical signals exist in the environment are resensed by the specialized mechanosensory cells, which convert the external forces into the electrical signals. Hearing is a magnificent example that relies on the mechanotransduction mediated by the auditory cells, for example the inner-ear hair cells in vertebrates and the Johnston's organ (JO) in fly. Previous studies have shown the fundamental physiological processes in the fly and vertebrate auditory organs are similar, suggesting that there might be a set of similar molecules underlying these processes. The molecular studies of the fly JO have been shown to be remarkably successful in discovering the developmental and functional genes that provided further implications in vertebrates. Several evolutionarily conserved molecules and signaling pathways have been shown to govern the development of the auditory organs in both vertebrates and invertebrates. The current review describes the similarities and differences between the vertebrate and fly auditory organs at developmental, structural, molecular, and transportation levels.
Collapse
Affiliation(s)
- Naveen Prakash Bokolia
- Department of Life Science, National Institute of Technology Rourkela, Rourkela, Orissa, India
| | | |
Collapse
|
9
|
Diverse cell type-specific mechanisms localize G protein-coupled receptors to Caenorhabditis elegans sensory cilia. Genetics 2014; 197:667-84. [PMID: 24646679 DOI: 10.1534/genetics.114.161349] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The localization of signaling molecules such as G protein-coupled receptors (GPCRs) to primary cilia is essential for correct signal transduction. Detailed studies over the past decade have begun to elucidate the diverse sequences and trafficking mechanisms that sort and transport GPCRs to the ciliary compartment. However, a systematic analysis of the pathways required for ciliary targeting of multiple GPCRs in different cell types in vivo has not been reported. Here we describe the sequences and proteins required to localize GPCRs to the cilia of the AWB and ASK sensory neuron types in Caenorhabditis elegans. We find that GPCRs expressed in AWB or ASK utilize conserved and novel sequences for ciliary localization, and that the requirement for a ciliary targeting sequence in a given GPCR is different in different neuron types. Consistent with the presence of multiple ciliary targeting sequences, we identify diverse proteins required for ciliary localization of individual GPCRs in AWB and ASK. In particular, we show that the TUB-1 Tubby protein is required for ciliary localization of a subset of GPCRs, implying that defects in GPCR localization may be causal to the metabolic phenotypes of tub-1 mutants. Together, our results describe a remarkable complexity of mechanisms that act in a protein- and cell-specific manner to localize GPCRs to cilia, and suggest that this diversity allows for precise regulation of GPCR-mediated signaling as a function of external and internal context.
Collapse
|
10
|
Park J, Lee J, Shim J, Han W, Lee J, Bae YC, Chung YD, Kim CH, Moon SJ. dTULP, the Drosophila melanogaster homolog of tubby, regulates transient receptor potential channel localization in cilia. PLoS Genet 2013; 9:e1003814. [PMID: 24068974 PMCID: PMC3778012 DOI: 10.1371/journal.pgen.1003814] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 07/23/2013] [Indexed: 12/27/2022] Open
Abstract
Mechanically gated ion channels convert sound into an electrical signal for the sense of hearing. In Drosophila melanogaster, several transient receptor potential (TRP) channels have been implicated to be involved in this process. TRPN (NompC) and TRPV (Inactive) channels are localized in the distal and proximal ciliary zones of auditory receptor neurons, respectively. This segregated ciliary localization suggests distinct roles in auditory transduction. However, the regulation of this localization is not fully understood. Here we show that the Drosophila Tubby homolog, King tubby (hereafter called dTULP) regulates ciliary localization of TRPs. dTULP-deficient flies show uncoordinated movement and complete loss of sound-evoked action potentials. Inactive and NompC are mislocalized in the cilia of auditory receptor neurons in the dTulp mutants, indicating that dTULP is required for proper cilia membrane protein localization. This is the first demonstration that dTULP regulates TRP channel localization in cilia, and suggests that dTULP is a protein that regulates ciliary neurosensory functions.
Collapse
Affiliation(s)
- Jina Park
- Department of Oral Biology, Yonsei University College of Dentistry, Seodaemun-gu, Seoul, Korea
| | - Jeongmi Lee
- Department of Life Science, University of Seoul, Seoul, Korea
| | - Jaewon Shim
- Department of Oral Biology, Yonsei University College of Dentistry, Seodaemun-gu, Seoul, Korea
| | - Woongsu Han
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jinu Lee
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Inchon, Korea
| | - Yong Chul Bae
- Department of Oral Anatomy and Neurobiology, BK21, School of Dentistry, Kyungpook National University, Daegu, Korea
| | - Yun Doo Chung
- Department of Life Science, University of Seoul, Seoul, Korea
| | - Chul Hoon Kim
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
- * E-mail: (CHK); (SJM)
| | - Seok Jun Moon
- Department of Oral Biology, Yonsei University College of Dentistry, Seodaemun-gu, Seoul, Korea
- * E-mail: (CHK); (SJM)
| |
Collapse
|