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Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder, causing defects of social interaction and repetitive behaviors. Here, we identify a de novo heterozygous gene-truncating mutation of the Sentrin-specific peptidase1 (SENP1) gene in people with ASD without neurodevelopmental delay. We find that Senp1+/- mice exhibit core autistic-like symptoms such as social deficits and repetitive behaviors but normal learning and memory ability. Moreover, we find that inhibitory and excitatory synaptic functions are severely affected in the retrosplenial agranular (RSA) cortex of Senp1+/- mice. Lack of Senp1 leads to increased SUMOylation and degradation of fragile X mental retardation protein (FMRP), also implicated in syndromic ASD. Importantly, re-introducing SENP1 or FMRP specifically in RSA fully rescues the defects of synaptic function and autistic-like symptoms of Senp1+/- mice. Together, these results demonstrate that disruption of the SENP1-FMRP regulatory axis in the RSA causes autistic symptoms, providing a candidate region for ASD pathophysiology.A variety of mechanosensory neurons are involved in touch, proprioception, and pain. Many molecular components of the mechanotransduction machinery subserving these sensory modalities remain to be discovered. Here, we combine recordings of mechanosensitive (MS) currents in mechanosensory neurons with single-cell RNA sequencing. Transcriptional profiles are mapped onto previously identified sensory neuron types to identify cell-type correlates between datasets. Correlation of current signatures with single-cell transcriptomes provides a one-to-one correspondence between mechanoelectric properties and transcriptomically defined neuronal populations. Moreover, a gene-expression differential comparison provides a set of candidate genes for mechanotransduction complexes. Piezo2 is expectedly found to be enriched in rapidly adapting MS current-expressing neurons, whereas Tmem120a and Tmem150c, thought to mediate slow-type MS currents, are uniformly expressed in all mechanosensory neuron subtypes. Further knockdown experiments disqualify them as mediating MS currents in sensory neurons. This dataset constitutes an open resource to explore further the cell-type-specific determinants of mechanosensory properties.Synaptonemal complex (SC) assembly and homologous recombination, the most critical events during prophase I, are the prerequisite for faithful meiotic chromosome segregation. However, the underlying regulatory mechanism remains largely unknown. Here, we reveal that a functional RING finger E3 ubiquitin ligase, DESYNAPSIS1 (DSNP1), plays significant roles in SC assembly and homologous recombination during rice meiosis. UBCS039 purchase In the dsnp1 mutant, homologous synapsis is discontinuous and aberrant SC-like polycomplexes occur independent of coaligned homologous chromosomes. Accompanying the decreased foci of HEI10, ZIP4, and MER3 on meiotic chromosomes, the number of crossovers (COs) decreases dramatically in dsnp1 meiocytes. Furthermore, the absence of central elements largely restores the localization of non-ZEP1 ZMM proteins and the number of COs in the dsnp1 background. Collectively, DSNP1 stabilizes the canonical tripartite SC structure along paired homologous chromosomes and further promotes the formation of COs.Ketamine is a noncompetitive glutamatergic N-methyl-d-aspartate receptor (NMDAR) antagonist that exerts rapid antidepressant effects. Preclinical studies identify eukaryotic elongation factor 2 kinase (eEF2K) signaling as essential for the rapid antidepressant action of ketamine. Here, we combine genetic, electrophysiological, and pharmacological strategies to investigate the role of eEF2K in synaptic function and find that acute, but not chronic, inhibition of eEF2K activity induces rapid synaptic scaling in the hippocampus. Retinoic acid (RA) signaling also elicits a similar form of rapid synaptic scaling in the hippocampus, which we observe is independent of eEF2K functioni. The RA signaling pathway is not required for ketamine-mediated antidepressant action; however, direct activation of the retinoic acid receptor α (RARα) evokes rapid antidepressant action resembling ketamine. Our findings show that ketamine and RARα activation independently elicit a similar form of multiplicative synaptic scaling that is causal for rapid antidepressant action.Despite the undisputable role of the small GTPase Rac1 in the regulation of actin cytoskeleton reorganization, the Rac guanine-nucleotide exchange factors (Rac-GEFs) involved in Rac1-mediated motility and invasion in human lung adenocarcinoma cells remain largely unknown. Here, we identify FARP1, ARHGEF39, and TIAM2 as essential Rac-GEFs responsible for Rac1-mediated lung cancer cell migration upon EGFR and c-Met activation. Noteworthily, these Rac-GEFs operate in a non-redundant manner by controlling distinctive aspects of ruffle dynamics formation. Mechanistic analysis reveals a leading role of the AXL-Gab1-PI3K axis in conferring pro-motility traits downstream of EGFR. Along with the positive association between the overexpression of Rac-GEFs and poor lung adenocarcinoma patient survival, we show that FARP1 and ARHGEF39 are upregulated in EpCam+ cells sorted from primary human lung adenocarcinomas. Overall, our study reveals fundamental insights into the complex intricacies underlying Rac-GEF-mediated cancer cell motility signaling, hence underscoring promising targets for metastatic lung cancer therapy.Fetal growth restriction (FGR) increases the risk for impaired cognitive function later in life. However, the precise mechanisms remain elusive. Using dexamethasone-induced FGR and protein restriction-influenced FGR mouse models, we observe learning and memory deficits in adult FGR offspring. FGR induces decreased hippocampal neurogenesis from the early post-natal period to adulthood by reducing the proliferation of neural stem cells (NSCs). We further find a persistent decrease of Tet1 expression in hippocampal NSCs of FGR mice. Mechanistically, Tet1 downregulation results in hypermethylation of the Dll3 and Notch1 promoters and inhibition of Notch signaling, leading to reduced NSC proliferation. Overexpression of Tet1 activates Notch signaling, offsets the decline in neurogenesis, and enhances learning and memory abilities in FGR offspring. Our data indicate that a long-term decrease in Tet1/Notch signaling in hippocampal NSCs contributes to impaired neurogenesis following FGR and could serve as potential targets for the intervention of FGR-related cognitive disorders.N-type voltage-gated calcium (CaV) channels mediate Ca2+ influx at presynaptic terminals in response to action potentials and play vital roles in synaptogenesis, release of neurotransmitters, and nociceptive transmission. Here, we elucidate a cryo-electron microscopy (cryo-EM) structure of the human CaV2.2 complex in apo, ziconotide-bound, and two CaV2.2-specific pore blockers-bound states. The second voltage-sensing domain (VSD) is captured in a resting-state conformation, trapped by a phosphatidylinositol 4,5-bisphosphate (PIP2) molecule, which is distinct from the other three VSDs of CaV2.2, as well as activated VSDs observed in previous structures of CaV channels. This structure reveals the molecular basis for the unique inactivation process of CaV2.2 channels, in which the intracellular gate formed by S6 helices is closed and a W-helix from the domain II-III linker stabilizes closed-state inactivation. The structures of this inactivated, drug-bound complex lay a solid foundation for developing new state-dependent blockers for treatment of chronic pain.Endocytosis and endosome dynamics are controlled by proteins of the small GTPase Rab family. Besides possible recycling routes to the plasma membrane and various organelles, previously described endocytic pathways (e.g., clathrin-mediated endocytosis, macropinocytosis, CLIC/GEEC pathway) all appear to funnel the endocytosed material to Rab5-positive early endosomes that then mature into Rab7-positive late endosomes/lysosomes. By studying the uptake of a series of cell-penetrating peptides (CPPs), we identify an endocytic pathway that moves material to nonacidic Lamp1-positive late endosomes. Trafficking via this endocytic route is fully independent of Rab5 and Rab7 but requires the Rab14 protein. The pathway taken by CPPs differs from the conventional Rab5-dependent endocytosis at the stage of vesicle formation already, as it is not affected by a series of compounds that inhibit macropinocytosis or clathrin-mediated endocytosis. The Rab14-dependent pathway is also used by physiological cationic molecules such as polyamines and homeodomains found in homeoproteins.Evidence for prefrontal cortical (PFC) GABAergic dysfunction is one of the most consistent findings in schizophrenia and may contribute to cognitive deficits. Recent studies suggest that the mGlu1 subtype of metabotropic glutamate receptor regulates cortical inhibition; however, understanding the mechanisms through which mGlu1 positive allosteric modulators (PAMs) regulate PFC microcircuit function and cognition is essential for advancing these potential therapeutics toward the clinic. We report a series of electrophysiology, optogenetic, pharmacological magnetic resonance imaging, and animal behavior studies demonstrating that activation of mGlu1 receptors increases inhibitory transmission in the prelimbic PFC by selective excitation of somatostatin-expressing interneurons (SST-INs). An mGlu1 PAM reverses cortical hyperactivity and concomitant cognitive deficits induced by N-methyl-d-aspartate (NMDA) receptor antagonists. Using in vivo optogenetics, we show that prelimbic SST-INs are necessary for mGlu1 PAM efficacy. Collectively, these findings suggest that mGlu1 PAMs could reverse cortical GABAergic deficits and exhibit efficacy in treating cognitive dysfunction in schizophrenia.Opiates produce a strong rewarding effect, but abstinence from opiate use emerges with severe negative emotions. Depression is one of the most frequent emotion disorders associated with opiate abstinence, which is thought to be a main cause for relapse. However, neurobiological bases of such an aversive emotion processing are poorly understood. Here, we find that morphine abstinence activates κ-opioid receptors (KORs) by increasing endogenous KOR ligand dynorphin expression in the amygdala, which in turn facilitates glutamate transporter 1 (GLT1) expression by activation of p38 mitogen-activated protein kinase (MAPK). Upregulation of GLT1 expression contributes to opiate-abstinence-elicited depressive-like behaviors through modulating amygdalar glutamatergic inputs to the nucleus accumbens (NAc). Intra-amygdala injection of GLT1 inhibitor DHK or knockdown of GLT1 expression in the amygdala significantly suppresses morphine-abstinence-induced depressive-like behaviors. Pharmacological and pharmacogenetic activation of amygdala-NAc projections prevents morphine-abstinence-induced behaviors. Overall, our study provides key molecular and circuit insights into the mechanisms of depression associated with opiate abstinence.Assembly and disassembly of DNA repair protein complexes at DNA damage sites are essential for maintaining genomic integrity. Investigating factors coordinating assembly of the base excision repair (BER) proteins DNA polymerase β (Polβ) and XRCC1 to DNA lesion sites identifies a role for Polβ in regulating XRCC1 disassembly from DNA repair complexes and, conversely, demonstrates Polβ's dependence on XRCC1 for complex assembly. LivePAR, a genetically encoded probe for live-cell imaging of poly(ADP-ribose) (PAR), reveals that Polβ and XRCC1 require PAR for repair-complex assembly, with PARP1 and PARP2 playing unique roles in complex dynamics. Further, BER complex assembly is modulated by attenuation/augmentation of NAD+ biosynthesis. Finally, SIRT6 does not modulate PARP1 or PARP2 activation but does regulate XRCC1 recruitment, leading to diminished Polβ abundance at sites of DNA damage. These findings highlight coordinated yet independent roles for PARP1, PARP2, and SIRT6 and their regulation by NAD+ bioavailability to facilitate BER.

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