The role of reversibility in the enantioselective conjugate addition of α,α-disubstituted aldehydes to nitro-olefins catalyzed by primary amine thioureas

2014 ◽  
Vol 4 (10) ◽  
pp. 3505-3509 ◽  
Author(s):  
Yining Ji ◽  
Donna G. Blackmond

Identification of intermediates in the asymmetric conjugate addition of aldehdyes to nitro-olefins catalyzed by primary amine thioureas add mechanistic insight.

Reproduction ◽  
2017 ◽  
Vol 154 (6) ◽  
pp. 723-733 ◽  
Author(s):  
Huijuan Zhang ◽  
Guishuan Wang ◽  
Lin Liu ◽  
Xiaolin Liang ◽  
Yu Lin ◽  
...  

The chromatoid body (CB) is a specific cloud-like structure in the cytoplasm of haploid spermatids. Recent findings indicate that CB is identified as a male germ cell-specific RNA storage and processing center, but its function has remained elusive for decades. In somatic cells, KH-type splicing regulatory protein (KSRP) is involved in regulating gene expression and maturation of select microRNAs (miRNAs). However, the function of KSRP in spermatogenesis remains unclear. In this study, we showed that KSRP partly localizes in CB, as a component of CB. KSRP interacts with proteins (mouse VASA homolog (MVH), polyadenylate-binding protein 1 (PABP1) and polyadenylate-binding protein 2 (PABP2)), mRNAs (Tnp2 and Odf1) and microRNAs (microRNA-182) in mouse CB. Moreover, KSRP may regulate the integrity of CB via DDX5-miRNA-182 pathway. In addition, we found abnormal expressions of CB component in testes of Ksrp-knockout mice and of patients with hypospermatogenesis. Thus, our results provide mechanistic insight into the role of KSRP in spermatogenesis.


Life Sciences ◽  
2022 ◽  
pp. 120299
Author(s):  
Mehdi Sanati ◽  
Samaneh Aminyavari ◽  
Amir R. Afshari ◽  
Amirhossein Sahebkar

2020 ◽  
Vol 56 (94) ◽  
pp. 14841-14844
Author(s):  
Dependu Dolui ◽  
Ab Qayoom Mir ◽  
Arnab Dutta

The photo- and electrocatalytic H2 production by the cobaloxime core improves in the presence of a primary amine group in the periphery.


2019 ◽  
Vol 317 (5) ◽  
pp. H1039-H1049 ◽  
Author(s):  
Lasse B. Steffensen ◽  
Cheryl A. Conover ◽  
Claus Oxvig

Pregnancy-associated plasma protein-A (PAPP-A) is a metalloproteinase with a well-established role in releasing bioactive insulin-like growth factor-1 (IGF-1) from IGF-binding protein-2, -4, and -5 by proteolytic processing of these. The IGF system has repeatedly been suggested to be involved in the pathology of atherosclerosis, and both PAPP-A and IGF-1 are proposed biomarkers and therapeutic targets for this disease. Several experimental approaches based on atherosclerosis mouse models have been undertaken to obtain causative and mechanistic insight to the role of these molecules in atherogenesis. However, reports seem conflicting. The literature suggests that PAPP-A is detrimental, while IGF-1 is beneficial. This raises important questions that need to be addressed. Here we summarize the various studies and discuss potential underlying explanations for this seemingly inconsistency with the objective of better understanding complexities and limitations when manipulating the IGF system in mouse models of atherosclerosis. A debate clarifying what’s up and what’s down is highly warranted going forward with the ultimate goal of improving atherosclerosis therapy by targeting the IGF system.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Brianna J. Klein ◽  
Suk Min Jang ◽  
Catherine Lachance ◽  
Wenyi Mi ◽  
Jie Lyu ◽  
...  

Abstract Acetylation of histone H3K23 has emerged as an essential posttranslational modification associated with cancer and learning and memory impairment, yet our understanding of this epigenetic mark remains insufficient. Here, we identify the native MORF complex as a histone H3K23-specific acetyltransferase and elucidate its mechanism of action. The acetyltransferase function of the catalytic MORF subunit is positively regulated by the DPF domain of MORF (MORFDPF). The crystal structure of MORFDPF in complex with crotonylated H3K14 peptide provides mechanistic insight into selectivity of this epigenetic reader and its ability to recognize both histone and DNA. ChIP data reveal the role of MORFDPF in MORF-dependent H3K23 acetylation of target genes. Mass spectrometry, biochemical and genomic analyses show co-existence of the H3K23ac and H3K14ac modifications in vitro and co-occupancy of the MORF complex, H3K23ac, and H3K14ac at specific loci in vivo. Our findings suggest a model in which interaction of MORFDPF with acylated H3K14 promotes acetylation of H3K23 by the native MORF complex to activate transcription.


2020 ◽  
Vol 11 (1) ◽  
pp. 257-263 ◽  
Author(s):  
Gianluca Casotti ◽  
Gianluca Ciancaleoni ◽  
Filippo Lipparini ◽  
Chiara Nieri ◽  
Anna Iuliano

The reaction mechanism of a new conjugate addition reaction of organozinc halides to enones is disclosed by a combined experimental/computational study.


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