Ethanolamine and Vinyl-Ether Moieties in Brain Phospholipids Modulate Behavior in Rats.

Plasmalogens are brain-enriched phospholipids with a vinyl-ether bond at the -1 position between the glycerol backbone and the alkyl chain. Previous studies have suggested that plasmalogens modulate locomotor activity, anxiety-like behavior, and cognitive functions in rodents; however, the specific moieties contributing to behavioral regulation are unknown. In this study, we examined the behavioral modulation induced by specific phospholipid moieties.

Knockout of the orphan membrane transporter Slc22a23 leads to a lean and hyperactive phenotype with a small hippocampal volume.

Epidemiological studies suggest that poor nutrition during pregnancy predisposes offspring to the development of lifestyle-related noncommunicable diseases and psychiatric disorders later in life. However, the molecular mechanisms underlying this predisposition are not well understood. In our previous study, using rats as model animals, we showed that behavioral impairments are induced by prenatal undernutrition.

Solitary and Synergistic Effects of Different Hydrophilic and Hydrophobic Phospholipid Moieties on Rat Behaviors.

Glycerophospholipids have hydrophobic and hydrophilic moieties. Previous studies suggest that phospholipids with different moieties have different effects on rodent behavior; however, the relationship between chemical structures and behavioral effects remains unclear. To clarify the functions of phospholipid moieties, we injected male rats with phospholipids with different moieties and conducted behavioral tests.

Excessive folic acid intake combined with undernutrition during gestation alters offspring behavior and brain monoamine profiles.

Dietary folic acid augmentation during gestation reduces neurodevelopmental disorder risk in offspring; however, it is still unclear if excessive maternal folic acid intake can impair brain function in offspring. We examined if excessive folic acid intake throughout gestation altered the behavior of male offspring under poor nutrition during early gestation (E5.5-E11.

Global pattern of interkinetic nuclear migration in tracheoesophageal epithelia of the mouse embryo: Interorgan and intraorgan regional differences.

Interkinetic nuclear migration (INM) is an apicobasal (AB) polarity-based regulatory mechanism of proliferation/differentiation in epithelial stem/progenitor cells. We previously documented INM in the endoderm-derived tracheal/esophageal epithelia at embryonic day (E) 11.5 and suggested that INM is involved in the development of both organs.

Correlation between musculoskeletal structure of the hand and primate locomotion: Morphometric and mechanical analysis in prehension using the cross- and triple-ratios.

Biometric ratios of the relative length of the rays in the hand have been analyzed between primate species in the light of their hand function or phylogeny. However, how relative lengths among phalanges are mechanically linked to the grasping function of primates with different locomotor behaviors remains unclear. To clarify this, we calculated cross and triple-ratios, which are related to the torque distribution, and the torque generation mode at different joint angles using the lengths of the phalanges and metacarpal bones in 52 primates belonging to 25 species.

Postweaning Iron Deficiency in Male Rats Leads to Long-Term Hyperactivity and Decreased Reelin Gene Expression in the Nucleus Accumbens.

Background: Epidemiological research indicates that iron deficiency (ID) in infancy correlates with long-term cognitive impairment and behavioral disturbances, despite therapy. However, the mechanisms underlying these effects are unknown.

Objective: We investigated how ID affected postweaning behavior and monoamine concentration in rat brains to determine whether ID during the juvenile period affected gene expression and synapse formation in the prefrontal cortex (PFC) and nucleus accumbens (NAcc).

Antibodies Set Boundaries Limiting Microbial Metabolite Penetration and the Resultant Mammalian Host Response.

Although the mammalian microbiota is well contained within the intestine, it profoundly shapes development and metabolism of almost every host organ. We questioned the range and depth of microbial metabolite penetration into the host, and how this is modulated by intestinal immunity. Chemically identical microbial and host metabolites were distinguished by stable isotope tracing from C-labeled live non-replicating Escherichia coli, differentiating C host isotopes with high-resolution mass spectrometry.

Complete Genome Sequences of 12 Species of Stable Defined Moderately Diverse Mouse Microbiota 2.

We report here the complete genome sequences of 12 bacterial species of stable defined moderately diverse mouse microbiota 2 (sDMDMm2) used to colonize germ-free mice with defined microbes. Whole-genome sequencing of these species was performed using the PacBio sequencing platform yielding circularized genome sequences of all 12 species.

The maternal microbiota drives early postnatal innate immune development.

Postnatal colonization of the body with microbes is assumed to be the main stimulus to postnatal immune development. By transiently colonizing pregnant female mice, we show that the maternal microbiota shapes the immune system of the offspring. Gestational colonization increases intestinal group 3 innate lymphoid cells and F4/80(+)CD11c(+) mononuclear cells in the pups.

REG-γ associates with and modulates the abundance of nuclear activation-induced deaminase.

Activation-induced deaminase (AID) acts on the immunoglobulin loci in activated B lymphocytes to initiate antibody gene diversification. The abundance of AID in the nucleus appears tightly regulated, with most nuclear AID being either degraded or exported back to the cytoplasm. To gain insight into the mechanisms regulating nuclear AID, we screened for proteins interacting specifically with it.

Stimulation of DNA Glycosylase Activities by XPC Protein Complex: Roles of Protein-Protein Interactions.

We showed that XPC complex, which is a DNA damage detector for nucleotide excision repair, stimulates activity of thymine DNA glycosylase (TDG) that initiates base excision repair. XPC appeared to facilitate the enzymatic turnover of TDG by promoting displacement from its own product abasic site, although the precise mechanism underlying this stimulation has not been clarified. Here we show that XPC has only marginal effects on the activity of E.

The p150 subunit of CAF-1 causes association of SUMO2/3 with the DNA replication foci.

The small ubiquitin-related modifier 2/3 (SUMO2/3) can be post-translationally conjugated to a wide variety of proteins constituting chromatin, the platform for genetic and epigenetic regulation. Nevertheless, it is unclear how SUMO2/3 and SUMO2/3-modified proteins are delivered to the chromatin fibers. Here we report that the largest subunit of chromatin assembly factor 1 (CAF-1), human p150, interacts directly and preferentially with SUMO2/3.

Structure of the small ubiquitin-like modifier (SUMO)-interacting motif of MBD1-containing chromatin-associated factor 1 bound to SUMO-3.

Post-translational modification by small ubiquitin-like modifier (SUMO) proteins has been implicated in the regulation of a variety of cellular events. The functions of sumoylation are often mediated by downstream effector proteins harboring SUMO-interacting motifs (SIMs) that are composed of a hydrophobic core and a stretch of acidic residues. MBD1-containing chromatin-associated factor 1 (MCAF1), a transcription repressor, interacts with SUMO-2/3 and SUMO-1, with a preference for SUMO-2/3.

Noncovalent binding of small ubiquitin-related modifier (SUMO) protease to SUMO is necessary for enzymatic activities and cell growth.

SUMO proteases possess two enzymatic activities to hydrolyze the C-terminal region of SUMOs (hydrolase activity) and to remove SUMO from SUMO-conjugated substrates (isopeptidase activity). SUMO proteases bind to SUMOs noncovalently, but the physiological roles of the binding in the functions of SUMO proteases are not well understood. In this study we found that SUMO proteases (Axam, SENP1, and yeast Ulp1) show different preferences for noncovalent binding to various SUMOs (SUMO-1, -2, -3, and yeast Smt3) and that the hydrolase and isopeptidase activities of SUMO proteases are dependent on their binding to SUMOs through salt bridge.

Inhibition of DNA binding of Sox2 by the SUMO conjugation.

Sox2 is a member of the high mobility group (HMG) domain DNA-binding proteins for transcriptional control and chromatin architecture. The HMG domain of Sox2 binds the DNA to facilitate transactivation by the cooperative transcription factors such as Oct3/4. We report that mouse Sox2 is modified by SUMO at lysine 247.

Involvement of SUMO modification in MBD1- and MCAF1-mediated heterochromatin formation.

Small ubiquitin-related modifiers, SUMO-2/3 and SUMO-1, are involved in gene regulation and nuclear structures. However, little is known about the roles of SUMO, in heterochromatin formation of mammalian cells. Here we demonstrate that SUMOs directly interact with human MCAF1, which forms complexes with either the methyl-CpG-binding protein MBD1 or SETDB1, which trimethylates histone H3 at lysine 9 (H3-K9) in the presence of MCAF1.

MafG sumoylation is required for active transcriptional repression.

A straightforward mechanism for eliciting transcriptional repression would be to simply block the DNA binding site for activators. Such passive repression is often mediated by transcription factors that lack an intrinsic repressor activity. MafG is a bidirectional regulator of transcription, a repressor in its homodimeric state but an activator when heterodimerized with p45.

In situ SUMOylation analysis reveals a modulatory role of RanBP2 in the nuclear rim and PML bodies.

SUMO modification plays a critical role in a number of cellular functions including nucleocytoplasmic transport, gene expression, cell cycle and formation of subnuclear structures such as promyelocytic leukemia (PML) bodies. In order to identify the sites where SUMOylation takes place in the cell, we developed an in situ SUMOylation assay using a semi-intact cell system and subsequently combined it with siRNA-based knockdown of nucleoporin RanBP2, also known as Nup358, which is one of the known SUMO E3 proteins. With the in situ SUMOylation assay, we found that both nuclear rim and PML bodies, besides mitotic apparatuses, are major targets for active SUMOylation.

Crystal structure of SUMO-3-modified thymine-DNA glycosylase.

Modification of cellular proteins by the small ubiquitin-like modifier SUMO is important in regulating various cellular events. Many different nuclear proteins are targeted by SUMO, and the functional consequences of this modification are diverse. For most proteins, however, the functional and structural consequences of modification by specific SUMO isomers are unclear.

Crystal structure of thymine DNA glycosylase conjugated to SUMO-1.

Members of the small ubiquitin-like modifier (SUMO) family can be covalently attached to the lysine residue of a target protein through an enzymatic pathway similar to that used in ubiquitin conjugation, and are involved in various cellular events that do not rely on degradative signalling via the proteasome or lysosome. However, little is known about the molecular mechanisms of SUMO-modification-induced protein functional transfer. During DNA mismatch repair, SUMO conjugation of the uracil/thymine DNA glycosylase TDG promotes the release of TDG from the abasic (AP) site created after base excision, and coordinates its transfer to AP endonuclease 1, which catalyses the next step in the repair pathway.

Generation of SUMO-1 modified proteins in E. coli: towards understanding the biochemistry/structural biology of the SUMO-1 pathway.

Here, we developed a binary vector system that introduces a synthetic SUMO-1 conjugation pathway into Escherichia coli and demonstrated that large amounts of sumoylated Ran GTPase activating protein 1 C-terminal region (RanGAP1-C2), Ran binding protein 2 internal repeat domain, p53 and promyelocytic leukemia were efficiently produced. The sumoylated recombinant RanGAP1-C2 appeared to retain the in vivo properties, since it was specifically sumoylated at lysine 517 as expected from in vivo studies. Our findings indicate the establishment of a biosynthetic route for producing large amounts of sumoylated recombinant proteins that will open up new avenues for studying the biochemical and structural aspects of the SUMO-1 modification pathway.

Serum response factor is modulated by the SUMO-1 conjugation system.

Serum stimulation leads to activation of the serum response factor (SRF)-mediated transcription of immediate-early genes such as c-fos via various signal transduction pathways. We have previously reported that promyelocytic leukemia protein (PML) is involved in the transcriptional regulation by SRF. PML is one of the well-known substrates for modification by small ubiquitin-related modifier-1 (SUMO-1) and several SUMO-1-modified proteins associate with PML.