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As a renewable energy, solar energy has aroused people’s attention and studies of this issue have become a hot topic throughout the world. How to turn solar energy into electric energy with a relatively better efficiency and lower costs has already become people’s new focus. Photovoltaic (PV) cell is such a new device that uses light to generate electricity. Among all of the PV products, the first-generation PV refers to silicon (Si) wafers with a power conversion efficiency (PCE) of 26%. However, these PV cells exhibit relatively high cost, limited conversion efficiency, and high processing cost. While, a new material called perovskite photovoltaic material came into people’s eyes. Perovskite materials exhibit variable structures, diversified composition and tubable performance. This material can help to improve the PCE into to a greater level, which is considered as the key performance of PV cells. This work introduces recent developments of halide perovskite and their performances as PV cells.

Posttranslational modification (PTM) is pivotal for regulating protein functions. Compared to acetylation on lysine residues, the functions and molecular mechanisms of N-terminal acetylation that occur on the first amino acids of proteins are less understood in the macroautophagy/autophagy field. We recently demonstrated that the B-type N-terminal acetyltransferase NatB, formed by the catalytic subunit Nat3 and auxiliary subunit Mdm20, is essential for autophagy. Deficiency of NatB causes blockage of autophagosome formation. We further identified the actin cytoskeleton constituent Act1 and dynamin-like GTPase Vps1 as substrates modified by NatB. The N-terminal acetylation of Act1 promotes its formation of actin filaments and thus facilitates trafficking of Atg9-containing vesicles for autophagosome formation, whereas N-terminal acetylation of Vps1 promotes its interaction with SNARE proteins and facilitates autophagosome-vacuole fusion. Restoring the N-terminal acetylation of Act and Vps1 does not restore autophagy in NatB-deleted cells, suggesting that additional substrates of NatB modification are involved in autophagy regulation.

BACKGROUND Kid (kinesin-like DNA binding protein), a member of microtubule-dependent molecular motor proteins, also known as KIF22, is reported to be associated with carcinogenesis and cancer progression in different types of malignant tumor, but the biologic behavior and clinical outcome of KIF22 in prostate cancer (PCa) has not been well studied. This study aimed to analyze the association between KIF22 and clinical outcome in PCa patients. MATERIAL AND METHODS The expression of KIF22 in tumor specimens compared with paired paracancerous tissue from 114 patients undergoing radical prostatectomy was detected by immunohistochemistry; results were verified using The Cancer Genome Atlas (TCGA) database. Subsequently, the relationship between KIF22 expression and clinical prognosis of PCa patients was then statistically analyzed. RESULTS Both immunohistochemistry and database analysis showed that KIF22 was obviously overexpressed in PCa tissues compared with paracancerous tissue. The overexpression of KIF22 at the protein level was significantly related to higher clinical stage (P=0.025), Gleason score (P=0.002), seminal vesicle invasion (P=0.007), and lymph node metastasis (P=0.009). Furthermore, with the overexpression of KIF22 mRNA level in PCa patients, the oncological prognosis of PCa patients was much poorer. CONCLUSIONS High-level expression of KIF22 was related to both tumor progression and adverse clinical outcome. For this reason, KIF22 may become a potential prognostic factor for PCa.

Summary: Acetyl ligation to the amino acids in a protein is an important posttranslational modification. However, in contrast to lysine acetylation, N-terminal acetylation is elusive in terms of its cellular functions. Here, we identify Nat3 as an N-terminal acetyltransferase essential for autophagy, a catabolic pathway for bulk transport and degradation of cytoplasmic components. We identify the actin cytoskeleton constituent Act1 and dynamin-like GTPase Vps1 (vacuolar protein sorting 1) as substrates for Nat3-mediated N-terminal acetylation of the first methionine. Acetylated Act1 forms actin filaments and therefore promotes the transport of Atg9 vesicles for autophagosome formation; acetylated Vps1 recruits and facilitates bundling of the SNARE (soluble N-ethylmaleimide-sensitive factor activating protein receptor) complex for autophagosome fusion with vacuoles. Abolishment of the N-terminal acetylation of Act1 and Vps1 is associated with blockage of upstream and downstream steps of the autophagy process. Therefore, our work shows that protein N-terminal acetylation plays a critical role in controlling autophagy by fine-tuning multiple steps in the process.

Acetyl (Ac-) ligation to the amino acids in a protein is an important post-translational modification to regulate protein functions. However, in contrast to lysine acetylation, the N-terminal acetylation is elusive for its cellular functions. Here, we identified Nat3 as an N-terminal acetyltransferase essential for autophagy, a catabolic pathway for bulk transport and degradation of cytoplasmic components. We identified the actin cytoskeleton constituent Act1 and dynamin-like GTPase Vps1 as substrates for Nat3 mediated N-terminal acetylation on the first methionine. Specifically, acetylated Act1 forms actin filaments and therefore promotes the transport of Atg9 vesicles for autophagosome formation; acetylated Vps1 recruits and facilitates bundling of SNARE complex for autophagosome fusion with vacuoles. Abolishment of the N-terminal acetylation of Act1 and Vps1 is associated with blockage of upstream and downstream steps of autophagy process respectively. Therefore, our work shows the first that protein N-terminal acetylation plays a critical and ancient role in controlling of autophagy by finetuning multiple steps of this process.

The selective targeting and disposal of solid protein aggregates are essential for cells to maintain protein homoeostasis. Autophagy receptors including p62, NBR1, Cue5/TOLLIP (CUET), and Tax1-binding protein 1 (TAX1BP1) proteins function in selective autophagy by targeting ubiquitinated aggregates through ubiquitin-binding domains. Here, we summarize previous beliefs and recent findings on selective receptors in aggregate autophagy. Since there are many reviews on selective autophagy receptors, we focus on their oligomerization, which enables receptors to function as pathway determinants and promotes phase separation.