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Rouchidane Eyitayo A, Boudier-Lemosquet A, Chaignepain S, Priault M, Manon S. Bcl-xL Is Spontaneously Inserted into Preassembled Nanodiscs and Stimulates Bax Insertion in a Cell-Free Protein Synthesis System. Biomolecules 2023; 13:876. [PMID: 37371456 DOI: 10.3390/biom13060876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/10/2023] [Accepted: 05/19/2023] [Indexed: 06/29/2023] Open
Abstract
The antiapoptotic protein Bcl-xL is a major regulator of cell death and survival, but many aspects of its functions remain elusive. It is mostly localized in the mitochondrial outer membrane (MOM) owing to its C-terminal hydrophobic α-helix. In order to gain further information about its membrane organization, we set up a model system combining cell-free protein synthesis and nanodisc insertion. We found that, contrary to its proapoptotic partner Bax, neosynthesized Bcl-xL was spontaneously inserted into nanodiscs. The deletion of the C-terminal α-helix of Bcl-xL prevented nanodisc insertion. We also found that nanodisc insertion protected Bcl-xL against the proteolysis of the 13 C-terminal residues that occurs during expression of Bcl-xL as a soluble protein in E. coli. Interestingly, we observed that Bcl-xL increased the insertion of Bax into nanodiscs, in a similar way to that which occurs in mitochondria. Cell-free synthesis in the presence of nanodiscs is, thus, a suitable model system to study the molecular aspects of the interaction between Bcl-xL and Bax during their membrane insertion.
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Affiliation(s)
- Akandé Rouchidane Eyitayo
- Institut de Biochimie et de Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, 33077 Bordeaux, France
| | - Axel Boudier-Lemosquet
- Institut de Biochimie et de Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, 33077 Bordeaux, France
| | - Stéphane Chaignepain
- Institut de Biochimie et de Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, 33077 Bordeaux, France
- Centre de Génomique Fonctionnelle de Bordeaux, Université de Bordeaux, 33077 Bordeaux, France
| | - Muriel Priault
- Institut de Biochimie et de Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, 33077 Bordeaux, France
| | - Stéphen Manon
- Institut de Biochimie et de Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, 33077 Bordeaux, France
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2
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Basu A. The interplay between apoptosis and cellular senescence: Bcl-2 family proteins as targets for cancer therapy. Pharmacol Ther 2021; 230:107943. [PMID: 34182005 DOI: 10.1016/j.pharmthera.2021.107943] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 04/30/2021] [Indexed: 02/07/2023]
Abstract
Cell death by apoptosis and permanent cell cycle arrest by senescence serve as barriers to the development of cancer. Chemotherapeutic agents not only induce apoptosis, they can also induce senescence known as therapy-induced senescence (TIS). There are, however, controversies whether TIS improves or worsens therapeutic outcome. Unlike apoptosis, which permanently removes cancer cells, senescent cells are metabolically active, and can contribute to tumor progression and relapse. If senescent cells are not cleared by the immune system or if cancer cells escape senescence, they may acquire resistance to apoptotic stimuli and become highly aggressive. Thus, there have been significant efforts in developing senolytics, drugs that target these pro-survival molecules to eliminate senescent cells. The anti-apoptotic Bcl-2 family proteins not only protect against cell death by apoptosis, but they also allow senescent cells to survive. While combining senolytics with chemotherapeutic drugs is an attractive approach, there are also limitations. Moreover, members of the Bcl-2 family have distinct effects on apoptosis and senescence. The purpose of this review article is to discuss recent literatures on how members of the Bcl-2 family orchestrate the interplay between apoptosis and senescence, and the challenges and progress in targeting these Bcl-2 family proteins for cancer therapy.
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Affiliation(s)
- Alakananda Basu
- Department of Microbiology, Immunology and Genetics, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
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3
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Abstract
Bcl-xL is a pro-survival protein of the Bcl2 family found in the mitochondrial membrane. Bcl-xL supports growth, development, and maturation of neurons, and it also prevents neuronal death during neurotoxic stimulation. This article reviews the mechanisms and upstream signaling that regulate the activity and abundance of Bcl-xL. Our team and others have reported that oxidative stress is a key regulator of intracellular Bcl-xL balance in neurons. Oxidative stress regulates synthesis, degradation, and activity of Bcl-xL and therefore neuronal function. During apoptosis, pro-apoptotic Bcl2 proteins such as Bax and Bak translocate to and oligomerize in the mitochondrial membrane. Formation of oligomers causes release of cytochrome c and activation of caspases that lead to neuronal death. Bcl-xL binds directly to pro-apoptotic Bcl2 proteins to block apoptotic signaling. Although anti-apoptotic roles of Bcl-xL have been well documented, an increasing number of studies in recent decades show that protein binding partners of Bcl-xL are not limited to Bcl2 proteins. Bcl-xL forms a complex with F1Fo ATP synthase, DJ-1, DRP1, IP3R, and the ryanodine receptor. These proteins support physiological processes in neurons such as growth and development and prevent neuronal damage by regulating mitochondrial ATP production, synapse formation, synaptic vesicle recycling, neurotransmission, and calcium signaling. However, under conditions of oxidative stress, Bcl-xL undergoes proteolytic cleavage thus lowering the abundance of functional Bcl-xL in neurons. Additionally, oxidative stress alters formation of Bcl-xL-mediated multiprotein complexes by regulating post-translational phosphorylation. Finally, oxidative stress regulates transcription factors that target the Bcl-x gene and alter accessibility of microRNA to mRNA influencing mRNA levels of Bcl-xL. In this review, we discussed how Bcl-xL supports the normal physiology of neurons, and how oxidative stress contributes to pathology by manipulating the dynamics of Bcl-xL production, degradation, and activity.
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Affiliation(s)
- Han-A Park
- Department of Human Nutrition and Hospitality Management, College of Human Environmental Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - Katheryn Broman
- Department of Human Nutrition and Hospitality Management, College of Human Environmental Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - Elizabeth A Jonas
- Department of Internal Medicine, Section of Endocrinology, Yale University, New Haven, CT, USA
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4
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Borrás C, Mas-Bargues C, Román-Domínguez A, Sanz-Ros J, Gimeno-Mallench L, Inglés M, Gambini J, Viña J. BCL-xL, a Mitochondrial Protein Involved in Successful Aging: From C. elegans to Human Centenarians. Int J Mol Sci 2020; 21:ijms21020418. [PMID: 31936510 PMCID: PMC7014191 DOI: 10.3390/ijms21020418] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/01/2020] [Accepted: 01/04/2020] [Indexed: 01/07/2023] Open
Abstract
B-Cell Lymphoma-extra-large (BCL-xL) is involved in longevity and successful aging, which indicates a role for BCL-xL in cell survival pathway regulation. Beyond its well described role as an inhibitor of apoptosis by preventing cytochrome c release, BCL-xL has also been related, indirectly, to autophagy and senescence pathways. Although in these latter cases, BCL-xL has dual roles, either activating or inhibiting, depending on the cell type and the specific conditions. Taken together, all these findings suggest a precise mechanism of action for BCL-xL, able to regulate the crosstalk between apoptosis, autophagy, and senescence, thus promoting cell survival or cell death. All three pathways can be both beneficial or detrimental depending on the circumstances. Thus, targeting BCL-xL would in turn be a "double-edge sword" and therefore, additional studies are needed to better comprehend this dual and apparently contradictory role of BCL-XL in longevity.
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Affiliation(s)
- Consuelo Borrás
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
- Correspondence:
| | - Cristina Mas-Bargues
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
| | - Aurora Román-Domínguez
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
| | - Jorge Sanz-Ros
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
| | - Lucia Gimeno-Mallench
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
| | - Marta Inglés
- Freshage Research Group, Department of Physiotherapy, Faculty of Physiotherapy, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain;
| | - Juan Gambini
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
| | - José Viña
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES, INCLIVA, Avenida Blasco Ibañez, 15 46010 Valencia, Spain; (C.M.-B.); (A.R.-D.); (J.S.-R.); (L.G.-M.); (J.G.); (J.V.)
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5
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Li M, Wang D, He J, Chen L, Li H. Bcl-X L: A multifunctional anti-apoptotic protein. Pharmacol Res 2020; 151:104547. [PMID: 31734345 DOI: 10.1016/j.phrs.2019.104547] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 12/16/2022]
Abstract
B-cell lymphoma-extra large (Bcl-XL) is one of the anti-apoptotic proteins of the Bcl-2 family that is localized in the mitochondria. Bcl-XL is one of the key regulators of apoptosis that can also regulate other important cellular functions. Bcl-XL is overexpressed in many cancers, and its inhibitors have shown good therapeutic effects. Bcl-XL interacts with Beclin 1, a key factor regulating autophagy. Bcl-XL is essential for the survival of neurons and plays protective roles in neuronal injuries. It can promote the growth of neurons and the correct formation of neural networks, enhance synaptic plasticity, and control neurotoxicity. Bcl-XL can also promote the transport of Ca2+ to mitochondria, increase the production of ATP, and improve metabolic efficiency. In addition, targeting Bcl-XL has shown potential value in autoimmune diseases and aging. In this review, we summarize the functions of Bcl-XL in cancer, autophagy, Ca2+ signaling, neuroprotection, neuronal growth and synaptic plasticity, energy metabolism, immunity, and senescence as revealed by investigations conducted in the past 10 years. Moreover, we list some inhibitors that have been developed based on the functions of Bcl-XL.
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Affiliation(s)
- Mingxue Li
- Wuya College of Innovation, School of Pharmaceutical Engineering, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Dun Wang
- Wuya College of Innovation, School of Pharmaceutical Engineering, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Jianhua He
- Wuya College of Innovation, School of Pharmaceutical Engineering, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Lixia Chen
- Wuya College of Innovation, School of Pharmaceutical Engineering, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China.
| | - Hua Li
- Wuya College of Innovation, School of Pharmaceutical Engineering, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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6
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Myosin IIA suppresses glioblastoma development in a mechanically sensitive manner. Proc Natl Acad Sci U S A 2019; 116:15550-15559. [PMID: 31235578 DOI: 10.1073/pnas.1902847116] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ability of glioblastoma to disperse through the brain contributes to its lethality, and blocking this behavior has been an appealing therapeutic approach. Although a number of proinvasive signaling pathways are active in glioblastoma, many are redundant, so targeting one can be overcome by activating another. However, these pathways converge on nonredundant components of the cytoskeleton, and we have shown that inhibiting one of these-the myosin II family of cytoskeletal motors-blocks glioblastoma invasion even with simultaneous activation of multiple upstream promigratory pathways. Myosin IIA and IIB are the most prevalent isoforms of myosin II in glioblastoma, and we now show that codeleting these myosins markedly impairs tumorigenesis and significantly prolongs survival in a rodent model of this disease. However, while targeting just myosin IIA also impairs tumor invasion, it surprisingly increases tumor proliferation in a manner that depends on environmental mechanics. On soft surfaces myosin IIA deletion enhances ERK1/2 activity, while on stiff surfaces it enhances the activity of NFκB, not only in glioblastoma but in triple-negative breast carcinoma and normal keratinocytes as well. We conclude myosin IIA suppresses tumorigenesis in at least two ways that are modulated by the mechanics of the tumor and its stroma. Our results also suggest that inhibiting tumor invasion can enhance tumor proliferation and that effective therapy requires targeting cellular components that drive both proliferation and invasion simultaneously.
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Haschka M, Karbon G, Fava LL, Villunger A. Perturbing mitosis for anti-cancer therapy: is cell death the only answer? EMBO Rep 2018; 19:e45440. [PMID: 29459486 PMCID: PMC5836099 DOI: 10.15252/embr.201745440] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 12/15/2017] [Accepted: 01/29/2018] [Indexed: 12/12/2022] Open
Abstract
Interfering with mitosis for cancer treatment is an old concept that has proven highly successful in the clinics. Microtubule poisons are used to treat patients with different types of blood or solid cancer since more than 20 years, but how these drugs achieve clinical response is still unclear. Arresting cells in mitosis can promote their demise, at least in a petri dish. Yet, at the molecular level, this type of cell death is poorly defined and cancer cells often find ways to escape. The signaling pathways activated can lead to mitotic slippage, cell death, or senescence. Therefore, any attempt to unravel the mechanistic action of microtubule poisons will have to investigate aspects of cell cycle control, cell death initiation in mitosis and after slippage, at single-cell resolution. Here, we discuss possible mechanisms and signaling pathways controlling cell death in mitosis or after escape from mitotic arrest, as well as secondary consequences of mitotic errors, particularly sterile inflammation, and finally address the question how clinical efficacy of anti-mitotic drugs may come about and could be improved.
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Affiliation(s)
- Manuel Haschka
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Gerlinde Karbon
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Luca L Fava
- Centre for Integrative Biology (CIBIO), University of Trento, Povo, Italy
| | - Andreas Villunger
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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8
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Beaumatin F, El Dhaybi M, Bobo C, Verdier M, Priault M. Bcl-x L deamidation and cancer: Charting the fame trajectories of legitimate child and hidden siblings. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017. [PMID: 28645514 DOI: 10.1016/j.bbamcr.2017.06.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Bcl-2 family proteins control programmed cell death through a complex network of interactions within and outside of this family, that are modulated by post-translational modifications (PTM). Bcl-xL, an anti-apoptotic member of this family, is overexpressed in a number of cancers, plays an important role in tumorigenesis and is correlated with drug resistance. Bcl-xL is susceptible to a number of different PTMs. Here, we focus on deamidation. We will first provide an overview of protein deamidation. We will then review how the apoptotic and autophagic functions of Bcl-xL are modified by this PTM, and how this impacts on its oncogenic properties. Possible therapeutic outcomes will also be discussed. Finally, we will highlight how the specific case of Bcl-xL deamidation provides groundings to revisit some concepts related to protein deamidation in general.
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Affiliation(s)
- Florian Beaumatin
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France
| | - Mohamad El Dhaybi
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 2, rue du Docteur Marcland, 87025 Limoges Cedex, France
| | - Claude Bobo
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France
| | - Mireille Verdier
- EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 2, rue du Docteur Marcland, 87025 Limoges Cedex, France
| | - Muriel Priault
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France.
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9
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Priya P, Maity A, Ghosh Dastidar S. The long unstructured region of Bcl-xl modulates its structural dynamics. Proteins 2017; 85:1567-1579. [PMID: 28486788 DOI: 10.1002/prot.25316] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/28/2017] [Accepted: 05/02/2017] [Indexed: 01/22/2023]
Abstract
Bcl-xl protein has a long unstructured loop attached to its structured region which joins two helices. The necessity to have this unstructured segment in Bcl-xl is not yet well understood. To what extent the unstructured segment can influence the dynamics of the structured region of protein, with potential to influence the function, has been investigated in this work. Molecular dynamics simulation and principal component analysis show how the loop affects the internal motions of the protein, particularly its ligand binding pocket. Generally an unstructured region in the structure would promote flexibility resulting entropic stability but in contrary, here it narrows down the conformational space of the structured region of protein that could be hypothesized to impact the functional precision. Effects of the loop propagate to the binding pocket through structural rearrangements of polar side chains. The immediate suspicion of possible impact of phosphorylation to modulate the function of the protein is proven to be a fact, as the phosphorylated S49 and S62 located on the large unstructured region are seen to perturb the electrostatic network of the structure; an observation that validates and clarifies the role of loop as a modulator through biophysical and biochemical mechanisms. Proteins 2017; 85:1567-1579. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Prerna Priya
- Bioinformatics Centre, Bose Institute, P-1/12 C.I.T Scheme VII M, Kolkata, 700054, India
| | - Atanu Maity
- Bioinformatics Centre, Bose Institute, P-1/12 C.I.T Scheme VII M, Kolkata, 700054, India
| | - Shubhra Ghosh Dastidar
- Bioinformatics Centre, Bose Institute, P-1/12 C.I.T Scheme VII M, Kolkata, 700054, India
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Baruah PS, Beauchemin M, Parker JA, Bertrand R. Expression of human Bcl-xL (Ser49) and (Ser62) mutants in Caenorhabditis elegans causes germline defects and aneuploidy. PLoS One 2017; 12:e0177413. [PMID: 28481930 PMCID: PMC5421811 DOI: 10.1371/journal.pone.0177413] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 04/26/2017] [Indexed: 11/18/2022] Open
Abstract
An interesting feature of Bcl-xL protein is the presence of an unstructured loop domain between α1 and α2 helices, a domain not essential for its anti-apoptotic function and absent in CED-9 protein. Within this domain, Bcl-xL undergoes dynamic phosphorylation and dephosphorylation at Ser49 and Ser62 during G2 and mitosis in human cells. Studies have revealed that when these residues are mutated, cells harbour mitotic defects, including chromosome mis-attachment, lagging, bridging and mis-segregation with, ultimately, chromosome instability and aneuploidy. We undertook genetic experiments in Caenorhabditis elegans to understand the importance of Bcl-xL (Ser49) and (Ser62) in vivo. Transgenic worms carrying single-site S49A, S62A, S49D, S62D and dual site S49/62A mutants were generated and their effects were analyzed in germlines of young adult worms. Worms expressing Bcl-xL variants showed decreased egg-laying and hatching potency, variations in the length of their mitotic regions but not of their transition zones, appearance of chromosomal abnormalities at their diplotene stages, and increased germline apoptosis, with the exception of the S62D variants. Some of these transgenic strains, particularly the Ser to Ala variants, also showed slight modulations of lifespan compared to their controls. In addition, RNAi experiments silencing expression of the various Bcl-xL variants reversed their effects in vivo. Our in vivo observations confirmed the importance of Ser49 and Ser62 within Bcl-xL loop domain in maintaining chromosome stability.
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Affiliation(s)
- Prasamit Saurav Baruah
- Centre de recherche, Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal (Québec) Canada
- Institut du cancer de Montréal, Montréal (Québec) Canada
| | - Myriam Beauchemin
- Centre de recherche, Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal (Québec) Canada
- Institut du cancer de Montréal, Montréal (Québec) Canada
| | - J. Alexander Parker
- Centre de recherche, Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal (Québec) Canada
- Département de neurosciences, Université de Montréal, Montréal (Québec) Canada
| | - Richard Bertrand
- Centre de recherche, Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal (Québec) Canada
- Institut du cancer de Montréal, Montréal (Québec) Canada
- Département de médecine et Spec. médicales, Université de Montréal, Montréal (Québec) Canada
- * E-mail:
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