RESUMO
Alcohol-associated social facilitation together with attenuated sensitivity to adverse alcohol effects play a substantial role in adolescent alcohol use and misuse, with adolescent females being more susceptible to adverse consequences of binge drinking than adolescent males. Adolescent rodents also demonstrate individual and sex differences in sensitivity to ethanol-induced social facilitation and social inhibition, therefore the current study was designed to identify neuronal activation patterns associated with ethanol-induced social facilitation and ethanol-induced social inhibition in male and female adolescent cFos-LacZ rats. Experimental subjects were given social interaction tests on postnatal day (P) 34, 36, and 38 after an acute challenge with 0, 0.5 and 0.75â¯g/kg ethanol, respectively, and ß-galactosidase (ß-gal) expression was assessed in brain tissue of subjects socially facilitated and socially inhibited by 0.75â¯g/kg ethanol. In females, positive correlations were evident between overall social activity and neuronal activation of seven out of 13 ROIs, including the prefrontal cortex and nucleus accumbens, with negative correlations evident in males. Assessments of neuronal activation patterns revealed drastic sex differences between ethanol responding phenotypes. In socially inhibited males, strong correlations were evident among almost all ROIs (90â¯%), with markedly fewer correlations among ROIs (38â¯%) seen in socially facilitated males. In contrast, interconnectivity in females inhibited by ethanol was only 10â¯% compared to nearly 60â¯% in facilitated subjects. However, hub analyses revealed convergence of brain regions in males and females, with the nucleus accumbens being a hub region in socially inhibited subjects. Taken together, these findings demonstrate individual and sex-related differences in responsiveness to acute ethanol in adolescent rats, with sex differences more evident in socially inhibited by ethanol adolescents than their socially facilitated counterparts.
Assuntos
Etanol , Caracteres Sexuais , Comportamento Social , Animais , Masculino , Feminino , Etanol/farmacologia , Etanol/administração & dosagem , Depressores do Sistema Nervoso Central/farmacologia , Depressores do Sistema Nervoso Central/administração & dosagem , Ratos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Interação Social/efeitos dos fármacos , Ratos Transgênicos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Inibição PsicológicaRESUMO
PINK1 loss-of-function mutations and exposure to mitochondrial toxins are causative for Parkinson's disease (PD) and Parkinsonism, respectively. We demonstrate that pathological α-synuclein deposition, the hallmark pathology of idiopathic PD, induces mitochondrial dysfunction, and impairs mitophagy as evidenced by the accumulation of the PINK1 substrate pS65-Ubiquitin (pUb). We discovered MTK458, a brain penetrant small molecule that binds to PINK1 and stabilizes its active complex, resulting in increased rates of mitophagy. Treatment with MTK458 mediates clearance of accumulated pUb and α-synuclein pathology in α-synuclein pathology models in vitro and in vivo. Our findings from preclinical PD models suggest that pharmacological activation of PINK1 warrants further clinical evaluation as a therapeutic strategy for disease modification in PD.
RESUMO
Motives related to the enhancement of the positive effects of alcohol on social activity within sexes are strongly associated with alcohol use disorder and are a major contributor to adolescent alcohol use and heavy drinking. This is particularly concerning given that heightened vulnerability of the developing adolescent brain. Despite this linkage, it is unknown how adolescent non-intoxicated social behavior relates to alcohol's effects on social responding, and how the social brain network differs in response within individuals that are socially facilitated or inhibited by alcohol. Sex effects for social facilitation and inhibition during adolescence are conserved in rodents in high and low drinkers, respectively. In the current study we used cFos-LacZ transgenic rats to evaluate behavior and related neural activity in male and female subjects that differed in their social facilitatory or social inhibitory response to ethanol. Subjects were assessed using social interaction on postnatal days 34, 36 and 38 after a 0, 0.5 and 0.75 g/kg ethanol challenge, respectively, with brain tissue being evaluated following the final social interaction. Subjects were binned into those that were socially facilitated or inhibited by ethanol using a tertile split within each sex. Results indicate that both males and females facilitated by ethanol display lower social activity in the absence of ethanol compared to socially inhibited subjects. Analyses of neural activity revealed that females exhibited differences in 54% of examined socially relevant brain regions of interest (ROIs) compared to only 8% in males, with neural activity in females socially inhibited by ethanol generally being lower than facilitated subjects. Analysis of socially relevant ROI neural activity to social behavior differed for select brain regions as a function of sex, with the prefrontal cortex and nucleus accumbens being negatively correlated in males, but positively correlated in females. Females displayed additional positive correlations in other ROIs, and sex differences were noted across the rostro-caudal claustrum axis. Importantly, neural activity largely did not correlate with locomotor activity. Functional network construction of social brain regions revealed further sex dissociable effects, with 90% interconnectivity in males socially inhibited by ethanol compared to 38% of facilitated subjects, whereas interconnectivity in females inhibited by ethanol was 10% compared to nearly 60% in facilitated subjects. However, hub analyses converged on similar brain regions in males and females, with the nucleus accumbens being a hub region in socially inhibited subjects, whereas the central amygdala was disconnected in facilitated subjects. Taken together, these findings support unified brain regions that contribute to social facilitation or inhibition from ethanol despite prominent sex differences in the social brain network.
RESUMO
Dedicated assembly factors orchestrate the stepwise production of many molecular machines, including the 28-subunit proteasome core particle (CP) that mediates protein degradation. Here we report cryo-electron microscopy reconstructions of seven recombinant human subcomplexes that visualize all five chaperones and the three active site propeptides across a wide swath of the assembly pathway. Comparison of these chaperone-bound intermediates and a matching mature CP reveals molecular mechanisms determining the order of successive subunit additions, as well as how proteasome subcomplexes and assembly factors structurally adapt upon progressive subunit incorporation to stabilize intermediates, facilitate the formation of subsequent intermediates and ultimately rearrange to coordinate proteolytic activation with gated access to active sites. This work establishes a methodologic approach for structural analysis of multiprotein complex assembly intermediates, illuminates specific functions of assembly factors and reveals conceptual principles underlying human proteasome biogenesis, thus providing an explanation for many previous biochemical and genetic observations.
Assuntos
Microscopia Crioeletrônica , Modelos Moleculares , Chaperonas Moleculares , Complexo de Endopeptidases do Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/química , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/química , Conformação ProteicaRESUMO
Nucleotide-binding domain and leucine-rich repeat pyrin-domain containing protein 3 (NLRP3) is an innate immune sensor that forms an inflammasome in response to various cellular stressors. Gain-of-function mutations in NLRP3 cause autoinflammatory diseases and NLRP3 signalling itself exacerbates the pathogenesis of many other human diseases. Despite considerable therapeutic interest, the primary drivers of NLRP3 activation remain controversial due to the diverse array of signals that are integrated through NLRP3. Here, we mapped subcellular proteome changes to lysosomes, mitochondrion, EEA1-positive endosomes, and Golgi caused by the NLRP3 inflammasome agonists nigericin and CL097. We identified several common disruptions to retrograde trafficking pathways, including COPI and Shiga toxin-related transport, in line with recent studies. We further characterized mouse NLRP3 trafficking throughout its activation using temporal proximity proteomics, which supports a recent model of NLRP3 recruitment to endosomes during inflammasome activation. Collectively, these findings provide additional granularity to our understanding of the molecular events driving NLRP3 activation and serve as a valuable resource for cell biological research. We have made our proteomics data accessible through an open-access Shiny browser to facilitate future research within the community, available at: https://harperlab.connect.hms.harvard.edu/inflame/. We will display anonymous peer review for this manuscript on pubpub.org (https://harperlab.pubpub.org/pub/nlrp3/) rather than a traditional journal. Moreover, we invite community feedback on the pubpub version of this manuscript, and we will address criticisms accordingly.
RESUMO
Lysosomal storage diseases (LSDs) comprised ~50 monogenic diseases characterized by the accumulation of cellular material in lysosomes and associated defects in lysosomal function, but systematic molecular phenotyping is lacking. Here, we develop a nanoflow-based multi-omic single-shot technology (nMOST) workflow allowing simultaneously quantify HeLa cell proteomes and lipidomes from more than two dozen LSD mutants, revealing diverse molecular phenotypes. Defects in delivery of ferritin and its autophagic receptor NCOA4 to lysosomes (ferritinophagy) were pronounced in NPC2-/- cells, which correlated with increased lyso-phosphatidylcholine species and multi-lamellar membrane structures visualized by cryo-electron-tomography. Ferritinophagy defects correlated with loss of mitochondrial cristae, MICOS-complex components, and electron transport chain complexes rich in iron-sulfur cluster proteins. Strikingly, mitochondrial defects were alleviated when iron was provided through the transferrin system. This resource reveals how defects in lysosomal function can impact mitochondrial homeostasis in trans and highlights nMOST as a discovery tool for illuminating molecular phenotypes across LSDs.
RESUMO
The endoplasmic reticulum (ER) employs a diverse proteome landscape to orchestrate many cellular functions, ranging from protein and lipid synthesis to calcium ion flux and inter-organelle communication. A case in point concerns the process of neurogenesis, where a refined tubular ER network is assembled via ER shaping proteins into the newly formed neuronal projections to create highly polarized dendrites and axons. Previous studies have suggested a role for autophagy in ER remodelling, as autophagy-deficient neurons in vivo display axonal ER accumulation within synaptic boutons, and the membrane-embedded ER-phagy receptor FAM134B has been genetically linked with human sensory and autonomic neuropathy. However, our understanding of the mechanisms underlying selective removal of the ER and the role of individual ER-phagy receptors is limited. Here we combine a genetically tractable induced neuron (iNeuron) system for monitoring ER remodelling during in vitro differentiation with proteomic and computational tools to create a quantitative landscape of ER proteome remodelling via selective autophagy. Through analysis of single and combinatorial ER-phagy receptor mutants, we delineate the extent to which each receptor contributes to both the magnitude and selectivity of ER protein clearance. We define specific subsets of ER membrane or lumenal proteins as preferred clients for distinct receptors. Using spatial sensors and flux reporters, we demonstrate receptor-specific autophagic capture of ER in axons, and directly visualize tubular ER membranes within autophagosomes in neuronal projections by cryo-electron tomography. This molecular inventory of ER proteome remodelling and versatile genetic toolkit provide a quantitative framework for understanding the contributions of individual ER-phagy receptors for reshaping ER during cell state transitions.
Assuntos
Proteoma , Proteômica , Humanos , Retículo Endoplasmático/metabolismo , Autofagia/fisiologia , Estresse do Retículo Endoplasmático , Proteínas de Transporte/metabolismo , NeurogêneseRESUMO
Reversible modification of target proteins by ubiquitin and ubiquitin-like proteins (UBLs) is widely used by eukaryotic cells to control protein fate and cell behaviour1. UFM1 is a UBL that predominantly modifies a single lysine residue on a single ribosomal protein, uL24 (also called RPL26), on ribosomes at the cytoplasmic surface of the endoplasmic reticulum (ER)2,3. UFM1 conjugation (UFMylation) facilitates the rescue of 60S ribosomal subunits (60S) that are released after ribosome-associated quality-control-mediated splitting of ribosomes that stall during co-translational translocation of secretory proteins into the ER3,4. Neither the molecular mechanism by which the UFMylation machinery achieves such precise target selection nor how this ribosomal modification promotes 60S rescue is known. Here we show that ribosome UFMylation in vivo occurs on free 60S and we present sequential cryo-electron microscopy snapshots of the heterotrimeric UFM1 E3 ligase (E3(UFM1)) engaging its substrate uL24. E3(UFM1) binds the L1 stalk, empty transfer RNA-binding sites and the peptidyl transferase centre through carboxy-terminal domains of UFL1, which results in uL24 modification more than 150 Å away. After catalysing UFM1 transfer, E3(UFM1) remains stably bound to its product, UFMylated 60S, forming a C-shaped clamp that extends all the way around the 60S from the transfer RNA-binding sites to the polypeptide tunnel exit. Our structural and biochemical analyses suggest a role for E3(UFM1) in post-termination release and recycling of the large ribosomal subunit from the ER membrane.
Assuntos
Retículo Endoplasmático , Processamento de Proteína Pós-Traducional , Subunidades Ribossômicas Maiores de Eucariotos , Ubiquitina-Proteína Ligases , Sítios de Ligação , Biocatálise , Microscopia Crioeletrônica , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Membranas Intracelulares/ultraestrutura , Peptidil Transferases/química , Peptidil Transferases/metabolismo , Peptidil Transferases/ultraestrutura , Ligação Proteica , Proteínas Ribossômicas/química , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/ultraestrutura , Subunidades Ribossômicas Maiores de Eucariotos/química , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/ultraestrutura , RNA de Transferência/metabolismo , Especificidade por Substrato , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/ultraestruturaRESUMO
Dedicated assembly factors orchestrate stepwise production of many molecular machines, including the 28-subunit proteasome core particle (CP) that mediates protein degradation. Here, we report cryo-EM reconstructions of seven recombinant human subcomplexes that visualize all five chaperones and the three active site propeptides across a wide swath of the assembly pathway. Comparison of these chaperone-bound intermediates and a matching mature CP reveals molecular mechanisms determining the order of successive subunit additions, and how proteasome subcomplexes and assembly factors structurally adapt upon progressive subunit incorporation to stabilize intermediates, facilitate the formation of subsequent intermediates, and ultimately rearrange to coordinate proteolytic activation with gated access to active sites. The structural findings reported here explain many previous biochemical and genetic observations. This work establishes a methodologic approach for structural analysis of multiprotein complex assembly intermediates, illuminates specific functions of assembly factors, and reveals conceptual principles underlying human proteasome biogenesis.
RESUMO
The synthesis of proteins as encoded in the genome depends critically on translational fidelity. Nevertheless, errors inevitably occur, and those that result in reading frame shifts are particularly consequential because the resulting polypeptides are typically nonfunctional. Despite the generally maladaptive impact of such errors, the proper decoding of certain mRNAs, including many viral mRNAs, depends on a process known as programmed ribosomal frameshifting. The fact that these programmed events, commonly involving a shift to the -1 frame, occur at specific evolutionarily optimized "slippery" sites has facilitated mechanistic investigation. By contrast, less is known about the scope and nature of error (i.e., nonprogrammed) frameshifting. Here, we examine error frameshifting by monitoring spontaneous frameshift events that suppress the effects of single base pair deletions affecting two unrelated test proteins. To map the precise sites of frameshifting, we developed a targeted mass spectrometry-based method called "translational tiling proteomics" for interrogating the full set of possible -1 slippage events that could produce the observed frameshift suppression. Surprisingly, such events occur at many sites along the transcripts, involving up to one half of the available codons. Only a subset of these resembled canonical "slippery" sites, implicating alternative mechanisms potentially involving noncognate mispairing events. Additionally, the aggregate frequency of these events (ranging from 1 to 10% in our test cases) was higher than we might have anticipated. Our findings point to an unexpected degree of mechanistic diversity among ribosomal frameshifting events and suggest that frameshifted products may contribute more significantly to the proteome than generally assumed.
Assuntos
Escherichia coli , Proteômica , Escherichia coli/genética , Escherichia coli/metabolismo , Mutação da Fase de Leitura/genética , Mudança da Fase de Leitura do Gene Ribossômico/genética , Códon/metabolismoRESUMO
Summary: UniProtKB is a publicly accessible database of annotated protein features for numerous organisms; however, globally extracting protein entry information for data visualization and categorization can be challenging. While the UniProtKB entry syntax maintains database consistency, it simultaneously obscures key terms within long character strings. To increase accessibility, UniProtExtractR is both an app and R package that extracts desired information across nine UniProtKB categories: DNA binding, Pathway, Transmembrane, Signal peptide, Protein families, Domain [FT], Motif, Involvement in disease, and Subcellular location [CC]. The app features interactive frequency tables that globally summarize both the original UniProtKB input query as well as the extracted/changed entry values. Moreover, UniProtExtractR includes a tractable mapping algorithm to define custom organelle-level resolution. UniProtExtractR exists as a freely accessible Shiny app that requires no coding experience as well as R package, the code of which is entirely open source. Availability and implementation: UniProtExtractR source code and user manual, including example files and troubleshooting, is available at https://github.com/alex-bio/UniProtExtractR. The Shiny app is hosted at https://harperlab.connect.hms.harvard.edu/uniprotextractR.
RESUMO
STUDY QUESTION: Which add-ons are safe and effective to be used in ART treatment? SUMMARY ANSWER: Forty-two recommendations were formulated on the use of add-ons in the diagnosis of fertility problems, the IVF laboratory and clinical management of IVF treatment. WHAT IS KNOWN ALREADY: The innovative nature of ART combined with the extremely high motivation of the patients has opened the door to the wide application of what has become known as 'add-ons' in reproductive medicine. These supplementary options are available to patients in addition to standard fertility procedures, typically incurring an additional cost. A diverse array of supplementary options is made available, encompassing tests, drugs, equipment, complementary or alternative therapies, laboratory procedures, and surgical interventions. These options share the common aim of stating to enhance pregnancy or live birth rates, mitigate the risk of miscarriage, or expedite the time to achieving pregnancy. STUDY DESIGN, SIZE, DURATION: ESHRE aimed to develop clinically relevant and evidence-based recommendations focusing on the safety and efficacy of add-ons currently used in fertility procedures in order to improve the quality of care for patients with infertility. PARTICIPANTS/MATERIALS, SETTING, METHODS: ESHRE appointed a European multidisciplinary working group consisting of practising clinicians, embryologists, and researchers who have demonstrated leadership and expertise in the care and research of infertility. Patient representatives were included in the working group. To ensure that the guidelines are evidence-based, the literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, recommendations were based on the professional experience and consensus of the working group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 46 independent international reviewers. A total of 272 comments were received and incorporated where relevant. MAIN RESULTS AND THE ROLE OF CHANCE: The multidisciplinary working group formulated 42 recommendations in three sections; diagnosis and diagnostic tests, laboratory tests and interventions, and clinical management. LIMITATIONS, REASONS FOR CAUTION: Of the 42 recommendations, none could be based on high-quality evidence and only four could be based on moderate-quality evidence, implicating that 95% of the recommendations are supported only by low-quality randomized controlled trials, observational data, professional experience, or consensus of the development group. WIDER IMPLICATIONS OF THE FINDINGS: These guidelines offer valuable direction for healthcare professionals who are responsible for the care of patients undergoing ART treatment for infertility. Their purpose is to promote safe and effective ART treatment, enabling patients to make informed decisions based on realistic expectations. The guidelines aim to ensure that patients are fully informed about the various treatment options available to them and the likelihood of any additional treatment or test to improve the chance of achieving a live birth. STUDY FUNDING/COMPETING INTEREST(S): All costs relating to the development process were covered from ESHRE funds. There was no external funding of the development process or manuscript production. K.L. reports speakers fees from Merck and was part of a research study by Vitrolife (unpaid). T.E. reports consulting fees from Gynemed, speakers fees from Gynemed and is part of the scientific advisory board of Hamilton Thorne. N.P.P. reports grants from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare, speakers fees from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare. S.R.H. declares being managing director of Fertility Europe, a not-for-profit organization receiving financial support from ESHRE. I.S. is a scientific advisor for and has stock options from Alife Health, is co-founder of IVFvision LTD (unpaid) and received speakers' fee from the 2023 ART Young Leader Prestige workshop in China. A.P. reports grants from Gedeon Richter, Ferring Pharmaceuticals and Merck A/S, consulting fees from Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos and Merck A/S, speakers fees from Gedeon Richter, Ferring Pharmaceuticals, Merck A/S, Theramex and Organon, travel fees from Gedeon Richter. The other authors disclosed no conflicts of interest. DISCLAIMER: This Good Practice Recommendations (GPRs) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation.ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or bedeemedinclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results.Theydo not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type.Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.
Assuntos
Infertilidade , Medicina Reprodutiva , Gravidez , Feminino , Humanos , Infertilidade/terapia , Coeficiente de Natalidade , Resultado do Tratamento , Preparações FarmacêuticasRESUMO
During nutrient stress, macroautophagy degrades cellular macromolecules, thereby providing biosynthetic building blocks while simultaneously remodelling the proteome1,2. Although the machinery responsible for initiation of macroautophagy has been well characterized3,4, our understanding of the extent to which individual proteins, protein complexes and organelles are selected for autophagic degradation, and the underlying targeting mechanisms, is limited. Here we use orthogonal proteomic strategies to provide a spatial proteome census of autophagic cargo during nutrient stress in mammalian cells. We find that macroautophagy has selectivity for recycling membrane-bound organelles (principally Golgi and endoplasmic reticulum). Through autophagic cargo prioritization, we identify a complex of membrane-embedded proteins, YIPF3 and YIPF4, as receptors for Golgiphagy. During nutrient stress, YIPF3 and YIPF4 interact with ATG8 proteins through LIR motifs and are mobilized into autophagosomes that traffic to lysosomes in a process that requires the canonical autophagic machinery. Cells lacking YIPF3 or YIPF4 are selectively defective in elimination of a specific cohort of Golgi membrane proteins during nutrient stress. Moreover, YIPF3 and YIPF4 play an analogous role in Golgi remodelling during programmed conversion of stem cells to the neuronal lineage in vitro. Collectively, the findings of this study reveal prioritization of membrane protein cargo during nutrient-stress-dependent proteome remodelling and identify a Golgi remodelling pathway that requires membrane-embedded receptors.
Assuntos
Autofagia , Complexo de Golgi , Proteínas de Membrana , Nutrientes , Proteoma , Animais , Autofagia/fisiologia , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Retículo Endoplasmático , Complexo de Golgi/metabolismo , Mamíferos/metabolismo , Proteínas de Membrana/metabolismo , Nutrientes/metabolismo , Proteoma/metabolismo , ProteômicaRESUMO
Survival of growing pigs through to slaughter age is not only a key driver of profitability but also has implications for animal welfare. Changing preweaning mortality by over 3% gives a similar change in profit per pig as changing postweaning mortality by 1%. There is significant scope to improve both traits through management and breeding to improve survival. The aim of this literature review was to explore the relationship between litter size and piglet birthweight and the detrimental impact this negative association has had on pig survival, along with genetic strategies that have been implemented in breeding programmes. It is suggested that the primary effect of litter size on mortality was indirect, through the effects of litter size on individual piglet birthweights. The circumstances affecting the litter a piglet was born into were the most important for determining the birthweight of individual piglets, rather than the genetic make-up of the individual piglet itself. Therefore, breeding programmes should include the average piglet birthweight of a litter (i.e., a sow trait) rather than individual piglet birthweight to maintain the weight of piglets at birth. The relative weighting of litter size and average piglet birthweight should be done in a manner that avoids selecting heavy pigs from small litters. Additional genetic strategies to improve survival include survival at the litter level, or survival of individual piglets or enhanced through the use of genomic information. At the litter level, litter size at day 5 and weaning can be considered as sow traits, but the use of these traits depends on the recording environment. At the individual piglet level, pre- and postweaning survival can be recorded as 0/1 traits and analysed directly. Although heritabilities are low for all these traits, genetic improvements can be made. For preweaning survival, the genes of the nurse sow are more important than the genes of the individual piglet. The nurse sow model captures both the lactation and gestation effects, and the information obtained when piglets born from different litters are reared together. However, once a piglet is weaned, its own genes became more important for the expression of postweaning mortality outcomes. Finally, for a successful selection programme, combining the average piglet birthweight at the litter level and mortality data based on individual piglet records (not solely birthweight) might yield the best response in piglet survival.
RESUMO
The endoplasmic reticulum (ER) employs a diverse proteome landscape to orchestrate many cellular functions ranging from protein and lipid synthesis to calcium ion flux and inter-organelle communication. A case in point concerns the process of neurogenesis: a refined tubular ER network is assembled via ER shaping proteins into the newly formed neuronal projections to create highly polarized dendrites and axons. Previous studies have suggested a role for autophagy in ER remodeling, as autophagy-deficient neurons in vivo display axonal ER accumulation within synaptic boutons, and the membrane-embedded ER-phagy receptor FAM134B has been genetically linked with human sensory and autonomic neuropathy. However, our understanding of the mechanisms underlying selective removal of ER and the role of individual ER-phagy receptors is limited. Here, we combine a genetically tractable induced neuron (iNeuron) system for monitoring ER remodeling during in vitro differentiation with proteomic and computational tools to create a quantitative landscape of ER proteome remodeling via selective autophagy. Through analysis of single and combinatorial ER-phagy receptor mutants, we delineate the extent to which each receptor contributes to both magnitude and selectivity of ER protein clearance. We define specific subsets of ER membrane or lumenal proteins as preferred clients for distinct receptors. Using spatial sensors and flux reporters, we demonstrate receptor-specific autophagic capture of ER in axons, and directly visualize tubular ER membranes within autophagosomes in neuronal projections by cryo-electron tomography. This molecular inventory of ER proteome remodeling and versatile genetic toolkit provides a quantitative framework for understanding contributions of individual ER-phagy receptors for reshaping ER during cell state transitions.
RESUMO
Binge drinking during adolescence can have behavioral and neurobiological consequences. We have previously found that adolescent intermittent ethanol (AIE) exposure produces sex-specific social alterations indexed via decreases of social investigation and/or social preference in rats. The prelimbic cortex (PrL) regulates social interaction, and alterations within the PrL resulting from AIE may contribute to social alterations. The current study sought to determine whether AIE-induced PrL dysfunction underlies decreases in social interaction evident in adulthood. We first examined social interaction-induced neuronal activation of the PrL and several other regions of interest (ROIs) implicated in social interaction. Adolescent male and female cFos-LacZ rats were exposed to water (control) or ethanol (4 g/kg, 25% v/v) via intragastric gavage every other day between postnatal day (P) 25 and 45 (total 11 exposures). Since cFos-LacZ rats express ß-galactosidase (ß-gal) as a proxy for Fos, activated cells that express of ß-gal can be inactivated by Daun02. In most ROIs, expression of ß-gal was elevated in socially tested adult rats relative to home cage controls, regardless of sex. However, decreased social interaction-induced ß-gal expression in AIE-exposed rats relative to controls was evident only in the PrL of males. A separate cohort underwent PrL cannulation surgery in adulthood and was subjected to Daun02-induced inactivation. Inactivation of PrL ensembles previously activated by social interaction reduced social investigation in control males, with no changes evident in AIE-exposed males or females. These findings highlight the role of the PrL in male social investigation and suggest an AIE-associated dysfunction of the PrL that may contribute to reduced social investigation following adolescent ethanol exposure.
Assuntos
Etanol , Neurônios , Ratos , Masculino , Feminino , Animais , Etanol/farmacologiaRESUMO
In a recent issue of Nature, González et al. and Foronda et al. examine the role of ubiquitin in autophagic capture of ER by ER-phagy. They propose that ubiquitylation of ER-phagy receptor FAM134B and ER-shaping protein ARL61PL1 promotes receptor clustering in nanodomains, which generates membrane curvature, facilitating autophagosomal capture.
Assuntos
Retículo Endoplasmático , Proteínas de Membrana , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Ubiquitina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Autofagia , Estresse do Retículo EndoplasmáticoRESUMO
The protein kinase PINK1 and ubiquitin ligase Parkin promote removal of damaged mitochondria via a feed-forward mechanism involving ubiquitin (Ub) phosphorylation (pUb), Parkin activation, and ubiquitylation of mitochondrial outer membrane proteins to support the recruitment of mitophagy receptors. The ubiquitin ligase substrate receptor FBXO7/PARK15 is mutated in an early-onset parkinsonian-pyramidal syndrome. Previous studies have proposed a role for FBXO7 in promoting Parkin-dependent mitophagy. Here, we systematically examine the involvement of FBXO7 in depolarization and mt UPR-dependent mitophagy in the well-established HeLa and induced-neurons cell systems. We find that FBXO7-/- cells have no demonstrable defect in: (i) kinetics of pUb accumulation, (ii) pUb puncta on mitochondria by super-resolution imaging, (iii) recruitment of Parkin and autophagy machinery to damaged mitochondria, (iv) mitophagic flux, and (v) mitochondrial clearance as quantified by global proteomics. Moreover, global proteomics of neurogenesis in the absence of FBXO7 reveals no obvious alterations in mitochondria or other organelles. These results argue against a general role for FBXO7 in Parkin-dependent mitophagy and point to the need for additional studies to define how FBXO7 mutations promote parkinsonian-pyramidal syndrome.
Assuntos
Proteínas F-Box , Mitofagia , Humanos , Células HeLa , Mitofagia/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/metabolismoRESUMO
While education about fertility is not intrinsically controversial, finding the right language to communicate the topic can be challenging, as there are several risks of unintended negative effects such as dissonance, anxiety, culpability, and stigma due to social norming. In this article, we share some of our learnings from promoting fertility awareness in the hope that they will inspire further debate and research on this topic. Starting from the ethical principles of respect for reproductive autonomy, avoiding harm (in terms of stigma or anxiety) and inclusivity, we have formulated five recommendations: (i) frame fertility awareness messages with (reproductive) autonomy in mind and aim to be inclusive of those who do not represent the traditional nuclear family; (ii) be empathetic and steer clear of blame; (iii) avoid scaremongering and offer a positive angle; (iv) give due consideration to both women and men in fertility health messaging; and (v) tailor the messages to particular contexts and audiences and develop resources in close collaboration with the target groups.