Search

Context-dependent dynamic histone modifications constitute a key epigenetic mechanism in gene regulation. The Rpd3S complex recognizes H3K36 trimethylation (H3K36me3) and deacetylates histones H3 and H4 at multiple sites across transcribed regions. Here we solved the cryo-EM structures of yeast Rpd3S in its free and H3K36me3-nucleosome bound states. We demonstrated a unique architecture of Rpd3S, in which two copies of Eaf3-Rco1 heterodimers are asymmetrically assembled with Rpd3 and Sin3 to form a catalytic core complex. Multivalent recognition of two H3K36me3 marks, nucleosomal and linker DNAs by Eaf3, Sin3 and Rco1 positions the catalytic center of Rpd3 next to the histone H4 N-terminal tail for deacetylation. In an alternative catalytic mode, combinatorial readout of unmethylated H3K4 and H3K36me3 by Rco1 and Eaf3 directs histone H3-specific deacetylation except for the registered H3K9ac. Collectively, our work illustrates dynamic and diverse modes of multivalent nucleosomal engagement and methylation-guided deacetylation by Rpd3S, highlighting the exquisite complexity of epigenetic regulation with delicately designed multi-subunit enzymatic machineries in transcription and beyond.

Turning Maneuverability is an important hydrodynamic performance of the wave glider, which can realize the position keeping, path tracking and steering obstacle avoidance in a reliable way. The influences on the maneuverability of the relevant parameters of the rudder are analyzed by using the Computational Fluid Dynamic (CFD) method in this paper. Through the analysis, the conclusions that the optimal rudder area ratio with 0.15 and the aspect ratio with 0.8 are drawn. Furthermore, the position and profile of the rudder are also analyzed. To verify the validation of the work, sea trial data of the “Black Pearl” wave glider is adopted and analyzed. The result shows that the simulation analysis of the turning maneuverability of submerged glider is correct. And the conclusions have great significance for improving the turning maneuverability of the wave glider and the parameter design of the submerged glider engineering prototype from the perspective of the engineering application.

Distributed energy trading system is a new business model of energy industry. Applying blockchain technology, energy supply contracts can be communicated directly between producers and consumers. However, blockchain is without any identity authentication and legitimate user identities are possibly forged if there is not any user identity authentication procedure in a trading system. In this paper, we design an authentication scheme for blockchain-based energy trading systems by using edge computing, including journalizing processes, registration, and identity authentication. In our scheme, each node has computing power, which can ensure the meter data can be processed locally or on the edge. In addition, the correctness and security analysis of the scheme are also given in this paper. The analysis shows that our scheme is unforgeability and can protect users’ privacy.

In this paper, we present an effective code-based linkable ring signature scheme based on Borromean ring signature. The security of the scheme is based on the hardness of Syndrome Decoding problem, General Syndrome Decoding problem and Codeword Finding problem. We prove that our scheme has all the properties that a linkable ring signature scheme should have: unforgeability, anonymity, linkability and non-slanderability. Efficiency analysis shows that our scheme has a smaller signature size than the existing scheme under the same security conditions. Furthermore, this signature scheme can be easily extended to multiple layers. That is, code-based multilayer linkable ring signature scheme can be obtained and used for transactions with multiple inputs.

The increasing trend in power consumption, mainly due to the rapid population growth, has resulted in grid outages and low-reliability grid connections. Renewable-based hybrid energy systems are one of the emerging alternatives for traditional and low-reliability grid connections. In this paper, a stand-alone hybrid energy system is proposed for a remote residential house. HOMER software is used for the optimisation of the proposed energy system. The main contribution of the paper is focused on considering two influential parameters, such as annual load growth and photovoltaic (PV) degradation rates in the optimal planning of the hybrid energy system. Simulation results indicate that considering influential parameters more realistic results, including system configuration, total net present cost (NPC) and optimal operation of the energy sources are achievable. Total NPC of the system obtained as 70,072 US$, which shows 52,029 US$ growth in comparison to the case neglected annual load growth and PV degradation rates. The optimum configuration benefits from higher penetration of renewable energy sources (RESs). Moreover, according to the comparison made with only-grid system, the proposed hybrid renewable-based energy system saves a large number of emissions. Based on the results, around 292,049.4202 kg emissions have been saved over 25 years of the project.

Block chain is a revolutionary new technology proposed in recent years. It has the characteristics of decentralization, non-tampering with transactions, and extremely low transaction costs. These characteristics coincide with the decentralization and market structure of distributed transportation system. In this paper, we give the concrete structure of a blockchain-based transportation scheme, including process of journalizing, registration, transaction process. In addition, the correctness and security analysis of the scheme are also given in this paper.

The histone variant H2A.Z is essential for maintaining embryonic stem cell (ESC) identity in part by keeping developmental genes in a poised bivalent state. However, how H2A.Z is deposited into the bivalent domains remains unknown. In mammals, two chromatin remodeling complexes, Tip60/p400 and SRCAP, exchange the canonical histone H2A for H2A.Z in the chromatin. Here we show that Glioma Amplified Sequence 41 (Gas41), a shared subunit of the two H2A.Z-depositing complexes, functions as a reader of histone lysine acetylation and recruits Tip60/p400 and SRCAP to deposit H2A.Z into specific chromatin regions including bivalent domains. The YEATS domain of Gas41 bound to acetylated histone H3K27 and H3K14 both in vitro and in cells. The crystal structure of the Gas41 YEATS domain in complex with the H3K27ac peptide revealed that, similar to the AF9 and ENL YEATS domains, Gas41 YEATS forms a serine-lined aromatic cage for acetyllysine recognition. Consistently, mutations in the aromatic residues of the Gas41 YEATS domain abrogated the interaction. In mouse ESCs, knockdown of Gas41 led to flattened morphology of ESC colonies, as the result of derepression of differentiation genes. Importantly, the abnormal morphology was rescued by expressing wild-type Gas41, but not the YEATS domain mutated counterpart that does not recognize histone acetylation. Mechanically, we found that Gas41 depletion led to reduction of H2A.Z levels and a concomitant reduction of H3K27me3 levels on bivalent domains. Together, our study reveals an essential role of the Gas41 YEATS domain in linking histone acetylation to H2A.Z deposition and maintenance of ESC identity.

Recognition of modified histones by “reader” proteins constitutes a key mechanism regulating diverse chromatin-associated processes important for normal and neoplastic development. We recently identified the YEATS domain as a novel acetyllysine-binding module; however, the functional importance of YEATS domain-containing proteins in human cancer remains largely unknown. Here, we show that the YEATS2 gene is highly amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell growth and survival. YEATS2 binds to acetylated histone H3 via its YEATS domain. The YEATS2-containing ATAC complex co-localizes with H3K27 acetylation (H3K27ac) on the promoters of actively transcribed genes. Depletion of YEATS2 or disruption of the interaction between its YEATS domain and acetylated histones reduces the ATAC complex-dependent promoter H3K9ac levels and deactivates the expression of essential genes. Taken together, our study identifies YEATS2 as a histone H3K27ac reader that regulates a transcriptional program essential for NSCLC tumorigenesis., Histone modification recognition is an important mechanism for gene expression regulation in cancer. Here, the authors identify YEATS2 as a histone H3K27ac reader, regulating a transcriptional program essential for tumorigenesis in human non-small cell lung cancer.

Recognition of histone covalent modifications by chromatin-binding protein modules (“readers”) constitutes a major mechanism for epigenetic regulation, typified by bromodomains that bind acetyllysine. Non-acetyl histone lysine acylations (e.g. crotonylation, butyrylation, propionylation etc.) have been recently identified, however readers that prefer these acylations have not been characterized. Here we report that the AF9 YEATS domain displays selectively higher binding affinity for crotonyl- over acetyl-lysine. Structural studies revealed an extended aromatic sandwiching cage with crotonyl-specificity arising from π-aromatic and hydrophobic interactions between crotonyl and aromatic rings. These features are conserved among the YEATS, but not the bromodomains. Utilizing a cell-based model, we showed that AF9 co-localizes with crotonylated histone H3 and positively regulates gene expression in a YEATS domain-dependent manner. Our studies define the evolutionarily conserved YEATS domain as a family of crotonyllysine readers and specifically demonstrate that the YEATS domain of AF9 directly links histone crotonylation to active transcription.