TMPRSS12 Functions in Meiosis and Spermiogenesis and Is Required for Male Fertility in Mice.

Serine proteases are involved in many physiological activities as initiators of proteolytic cascades, and some members have been reported to play roles in male reproduction. Transmembrane serine protease 12 (TMPRSS12) has been shown to regulate sperm motility and uterotubal junction migration in mice, but its role in the testis remains unknown. In this study, we verified that TMPRSS12 was expressed in the spermatocytes and spermatids of testis and the acrosome of sperm. Mice deficient in Tmprss12 exhibited male sterility. In meiosis, TMPRSS12 was demonstrated to regulate synapsis and double-strand break repair; spermatocytes of Tmprss12 -/- mice underwent impaired meiosis and subsequent apoptosis, resulting in reduced sperm counts. During spermiogenesis, TMPRSS12 was found to function in the development of mitochondria; abnormal mitochondrial structure in Tmprss12 -/- sperm led to reduced availability of ATP, impacting sperm motility. The differential protein expression profiles of testes in Tmprss12 -/- and wild-type mice and further molecule identification revealed potential targets of TMPRSS12 related to meiosis and mitochondrial function. Besides, TMPRSS12 was also found to be involved in a series of sperm functions, including capacitation, acrosome reaction and sperm-egg interaction. These data imply that TMPRSS12 plays a role in multiple aspects of male reproduction.

Catalytic Oxidative C-H Annulation of Arylthiol Derivatives with 1,3-Diynes toward 3,3'-Bibenzothiophenes.

Disclosed herein is a catalytic oxidative C-H annulation of thiophenol derivatives with 1,3-diynes, which provides an efficient synthetic approach to both symmetrical and nonsymmetrical 3,3'-bibenzothiophenes. This protocol exhibits a broad substrate scope, excellent functional group tolerance, high regioselectivity, and catalyst-enabled switchable mono/diannulation selectivity. Moreover, three novel helical-type bithiophene heptagonal imides, which are potentially applicable in optoelectronic materials, are constructed based on this reaction.

Cyclin-dependent kinase 7 is essential for spermatogenesis by regulating retinoic acid signaling pathways and the STAT3 molecular pathway.

Spermatogenesis is a complex process that requires precise regulation. Phosphorylation plays a role in spermatogenesis by regulating protein structure and activity. This study focused on cyclin-dependent kinase 7 (CDK7), and explored its function and molecular mechanisms in spermatogenesis in vitro in a cell line and in vivo in a mouse model. Inhibition of CDK7 activity affected spermatogonia proliferation and differentiation, and we found that CDK7 regulates retinoic acid (RA)-mediated c-KIT expression to play a role in spermatogonia. Then, we demonstrated that inhibition of CDK7 affected meiosis initiation, DNA repair, and synaptonemal complex formation in meiosis progression, and CDK7 played this role by regulating RA-mediated STRA8 and REC8 signaling pathways. Moreover, inhibition of CDK7 impacted spermatid differentiation and resulted in decreased counts, decreased motility, and increased head deformity of sperm. We demonstrated that CDK7 affects germ cell apoptosis and sperm motility by activating STAT3 and that STAT3 further regulates Cortactin expression to influence the nuclear elongation, chromatin condensation, and acrosome formation of sperm. Additionally, EP300 was identified as another potential target phosphorylated by CDK7 that participates in chromatin condensation. Our results demonstrated the important role of CDK7 in all key aspects of spermatogenesis, potentially providing an effective target for clinical diagnosis and pathogenesis.

Ultralong room-temperature phosphorescence remarkably weakened by halogenation-induced molecular packing in hexaphenylmelamine derivatives.

A series of pure organic halogenated hexaphenylmelamine (HPM) derivatives featuring remarkably weakened ultralong room-temperature phosphorescence (RTP) were meticulously investigated. As the p-substituted atoms of these HPM derivatives sequentially changed from H to F, Cl and Br, both the RTP lifetimes and efficiencies dramatically decreased from 608 ms with 13.4% (HPM-H) to 337 ms with 5.3% (HPM-F), 99 ms with 1.3% (HPM-Cl), and 2.8 ms with undetectable efficiency (HPM-Br), respectively. Most notably, the severely weakened efficiencies are fundamentally different from the trends of the effect of halogenation on phosphorescence properties previously reported. Coupled with experimental results and theoretical simulations, the subtle change of molecular packing induced by halogenation should be responsible for the distinctive RTP properties. This finding not only provides a unique halogen-involved RTP phenomenon, but also offers a very special perspective to understand the effect of halogenation on phosphorescence.

MED1 is a lipogenesis coactivator required for postnatal adipose expansion.

MED1 often serves as a surrogate of the general transcription coactivator complex Mediator for identifying active enhancers. MED1 is required for phenotypic conversion of fibroblasts to adipocytes in vitro, but its role in adipose development and expansion in vivo has not been reported. Here, we show that MED1 is not generally required for transcription during adipogenesis in culture and that MED1 is dispensable for adipose development in mice. Instead, MED1 is required for postnatal adipose expansion and the induction of fatty acid and triglyceride synthesis genes after pups switch diet from high-fat maternal milk to carbohydrate-based chow. During adipogenesis, MED1 is dispensable for induction of lineage-determining transcription factors (TFs) PPARγ and C/EBPα but is required for lipid accumulation in the late phase of differentiation. Mechanistically, MED1 controls the induction of lipogenesis genes by facilitating lipogenic TF ChREBP- and SREBP1a-dependent recruitment of Mediator to active enhancers. Together, our findings identify a cell- and gene-specific regulatory role of MED1 as a lipogenesis coactivator required for postnatal adipose expansion.

MacroH2A1.1 cooperates with EZH2 to promote adipogenesis by regulating Wnt signaling.

White adipocytes play important roles in many physiological processes, including energy storage, endocrine signaling, and inflammatory responses. Understanding the molecular mechanisms of adipocyte formation (adipogenesis) provides insights into therapeutic approaches against obesity and its related diseases. Many transcriptional factors and epigenetic enzymes are known to regulate adipogenesis; however, whether histone variants play a role in this process is unknown. Here we found that macroH2A1.1 (mH2A1.1), a variant of histone H2A, was upregulated during adipocyte differentiation in 3T3-L1 cells and in the white adipose tissue of obese mice. Ablation of mH2A1.1 activated Wnt/ß-catenin signaling pathway, while overexpression of mH2A1.1 showed opposite effects. We further found that mH2A1.1 regulated Wnt/ß-catenin signaling pathway by cooperating with EZH2, a histone H3K27 methyltransferase, thus led to accumulation of H3K27me2 and H3K27me3 on the promoters of Wnt genes. Mutations in the macro-domain, mH2A1.1G224E, and mH2A1.1G314E, not only impaired adipogenesis, but also impaired the binding ability of mH2A1.1 to EZH2 and the enrichments of H3K27me2 and H3K27me3 on the promoters of Wnt genes. Together, our study reveals a novel regulatory role of mH2A1.1 in adipogenesis and obesity, which provides new insights in white fat development.

Rh(III)-Catalyzed Regio- and Chemoselective [4 + 1]-Annulation of Azoxy Compounds with Diazoesters for the Synthesis of 2H-Indazoles: Roles of the Azoxy Oxygen Atom.

A Rh(III)-catalyzed tandem C-H alkylation/intramolecular decarboxylative cyclization of azoxy compounds with diazoesters for the synthesis of 3-acyl-2H-indazoles is disclosed. The azoxy instead of the azo group enables a distinct approach for cyclative capture, leading to a [4 + 1]-annulation rather than a classic [4 + 2] manner. The azoxy oxygen atom is traceless after annulation, and further removal from the product is not required. This reaction features a complete regioselectivity for unsymmetrical azoxybenzenes and a compatibility of monoaryldiazene oxides.

Histone HIST1H1C/H1.2 regulates autophagy in the development of diabetic retinopathy.

Autophagy plays critical and complex roles in many human diseases, including diabetes and its complications. However, the role of autophagy in the development of diabetic retinopathy remains uncertain. Core histone modifications have been reported involved in the development of diabetic retinopathy, but little is known about the histone variants. Here, we observed increased autophagy and histone HIST1H1C/H1.2, an important variant of the linker histone H1, in the retinas of type 1 diabetic rodents. Overexpression of histone HIST1H1C upregulates SIRT1 and HDAC1 to maintain the deacetylation status of H4K16, leads to upregulation of ATG proteins, then promotes autophagy in cultured retinal cell line. Histone HIST1H1C overexpression also promotes inflammation and cell toxicity in vitro. Knockdown of histone HIST1H1C reduces both the basal and stresses (including high glucose)-induced autophagy, and inhibits high glucose induced inflammation and cell toxicity. Importantly, AAV-mediated histone HIST1H1C overexpression in the retinas leads to increased autophagy, inflammation, glial activation and neuron loss, similar to the pathological changes identified in the early stage of diabetic retinopathy. Furthermore, knockdown of histone Hist1h1c by siRNA in the retinas of diabetic mice significantly attenuated the diabetes-induced autophagy, inflammation, glial activation and neuron loss. These results indicate that histone HIST1H1C may offer a novel therapeutic target for preventing diabetic retinopathy.

Palladium-Catalyzed Annulation of Internal Alkynes: Direct Access to π-Conjugated Ullazines.

A palladium-catalyzed cyclization reaction of 1-(2,6-dibromophenyl)-1H-pyrroles with alkynes has been developed to construct various π-conjugated indolizino[6,5,4,3-ija]quinolones (ullazines) with a reactive functional group tolerance. As illustrative examples, three new ullazine-based sensitizers are synthesized, and the performance of these dyes is examined in DSSC devices, which demonstrates the potential of direct C-H functionalization in the construction of organic optoelectronic materials.

Rhodium-catalyzed annulation of arenes with alkynes through weak chelation-assisted C-H activation.

The purpose of this article is to give a brief review of weak chelation-assistance as a powerful means for the rhodium-catalyzed annulation of arenes with alkynes. The use of commonly occurring functional groups (e.g., ketones, aldehydes, carboxylic acids and alcohols) as the directing groups enriches the versatility of auxiliary ligands and extends the scope of products. This short article offers an overview on emerging procedures, highlights their advantages and limitations, and covers the latest progress in the rapid synthesis of organic functional materials and natural products.

Nickel-Catalyzed Addition-Type Alkenylation of Unactivated, Aliphatic C-H Bonds with Alkynes: A Concise Route to Polysubstituted γ-Butyrolactones.

Through the nickel-catalyzed chelation-assisted C-H bond activation strategy, the addition-type alkenylation of unreactive ß-C(sp(3))-H bonds of aliphatic amides with internal alkynes is developed for the first time to produce γ,δ-unsaturated carboxylic amide derivatives. The resulting alkenylated products can further be transformed into polysubstituted γ-butyrolactones with pyridinium chlorochromate (PCC).

Apelin protects against acute renal injury by inhibiting TGF-ß1.

Renal ischemia/reperfusion (I/R) injury is the most common cause of acute kidney injury, having a high rate of mortality and no effective therapy currently available. Apelin-13, a bioactive peptide, has been shown to inhibit the early lesions of diabetic nephropathy in several mouse models by us and others. To test whether apelin-13 protects against renal I/R induced injury, male rats were exposed to renal I/R injury with or without apelin-13 treatment for 3 days. Apelin-13 treatment markedly reduced the injury-induced tubular lesions, renal cell apoptosis, and normalized the injury induced renal dysfunction. Apelin-13 treatment inhibited the injury-induced elevation of inflammatory factors and Tgf-ß1, as well as apoptosis. Apelin-13 treatment also inhibited the injury-induced elevation of histone methylation and Kmt2d, a histone methyltransferase of H3K4me2, following renal I/R injury. Furthermore, in cultured renal mesangial and tubular cells, apelin-13 suppressed the injury-induced elevation of Tgf-ß1, apoptosis, H3K4me2 and Kmt2d under the in vitro hypoxia/reperfusion (H/R) conditions. Consistently, over-expression of apelin significantly inhibited H/R-induced elevation of TGF-ß1, apoptosis, H3K4me2 and Kmt2d. The present study therefore suggests apelin-13 may be a therapeutic candidate for treating acute kidney injury.

Histone acetyltransferase PCAF regulates inflammatory molecules in the development of renal injury.

Kidney diseases, including chronic kidney disease (CKD) and acute kidney injury (AKI), are associated with inflammation. The mechanism that regulates inflammation in these renal injuries remains unclear. Here, we demonstrated that p300/CBP-associated factor (PCAF), a histone acetyltransferase, was overexpressed in the kidneys of db/db mice and lipopolysaccharide (LPS)-injected mice. Moreover, elevated histone acetylation, such as H3K18ac, and up-regulation of some inflammatory genes, such as ICAM-1, VCAM-1, and MCP-1, were found upon these renal injuries. Furthermore, increased H3K18ac was recruited to the promoters of ICAM-1, VCAM-1, and MCP-1 in the kidneys of LPS-injected mice. In vitro studies demonstrated that PCAF knockdown in human renal proximal tubule epithelial cells (HK-2) led to downregulation of inflammatory molecules, including VCAM-1, ICAM-1, p50 subunit of NF-κB (p50), and MCP-1 mRNA and protein levels, together with significantly decreased H3K18ac level. Consistent with these, overexpression of PCAF enhanced the expression of inflammatory molecules. Furthermore, PCAF deficiency reduced palmitate-induced recruitment of H3K18ac on the promoters of ICAM-1 and MCP-1, as well as inhibited palmitate-induced upregulation of these inflammatory molecules. In summary, the present work demonstrates that PCAF plays an essential role in the regulation of inflammatory molecules through H3K18ac, which provides a potential therapeutic target for inflammation-related renal diseases.

Modular establishment of a diketopyrrolopyrrole-based polymer library via Pd-catalyzed direct C-H (Hetero)arylation: a highly efficient approach to discover low-bandgap polymers.

A concise, highly efficient palladium-catalyzed direct C-H (hetero)arylation is developed to modularly assemble a diketopyrrolopyrrole (DTDPP)-based polymer library to screen low-bandgap and near-infrared (NIR) absorbing materials. The DTDPP-based copolymers P1 and P2 with an alternating donor-acceptor-donor-acceptor (D-A-D-A) sequence and the homopolymer P9 exhibit planarity and excellent π-conjugation, which lead to low bandgaps (down to 1.22 eV) as well as strong and broad NIR absorption bands (up to 1000 nm).

Palladium(II)-catalyzed oxidative C-H/C-H cross-coupling between two structurally similar azoles.

Power of two: A widely functional-group tolerant, selective and rapid oxidative cross-coupling between two structurally similar azoles has been carried out by using a palladium/copper co-catalytic twofold C-H activation method (see scheme).