Therapeutic effects of a novel synthetic α-secretase.

Excessive accumulation of amyloid-β (Aβ) has been associated with the pathogenesis of Alzheimer's disease (AD). Clinical studies have further proven that elimination of Aβ can be a viable therapeutic option. In the current study, we conceptualized a fusion membrane protein, referred to as synthetic α-secretase (SAS), that can cleave amyloid precursor protein (APP) and Aβ specifically at the α-site.

Ubiquitin-conjugating enzyme V variant 1 enables cellular responses toward fibroblast growth factor signaling in endothelium.

Ubiquitination has been shown to provide an essential regulatory role in modulating the duration and amplitude of the signaling activity in angiogenesis. While successive enzymatic reactions mediated by three distinct types of enzymes commonly known as E1, E2, and E3 are required for ubiquitination, the role of E3s which govern the final step of ubiquitination has been extensively analyzed in angiogenesis. In contrast, the role of E2s, which determine the context and functional consequences of ubiquitination, remains largely unknown with respect to angiogenesis.

The role of ubiquitin-conjugating enzyme Ube2j1 phosphorylation and its degradation by proteasome during endoplasmic stress recovery.

The human Ube2j1 and Ube2j2 are the only ubiquitin-conjugating enzymes (E2s) that are localized to endoplasmic reticulum (ER) through its C-terminal transmembrane domains. Ube2j1 is a known substrate of MAPK signalling pathway and it is phosphorylated at serine-184 during ER stress. Here, we demonstrate that Ube2j1, not Ube2j2 is essential for the recovery of cells from transient ER stress.

Evaluation of simple pre-determined length insertion technique (SPLIT) with conventional method for oral fibreoptic intubation: A randomised cross-over study.

Background And Aims: The difficulty during flexible fiber-optic bronchoscopy (FOB) guided tracheal intubation could be because of inability in visualising glottis, advancing and railroading of endotracheal tube. Several methods are available for visualising glottis, but none is ideal. Hence, this randomised controlled study was designed to evaluate the simple pre-determined length insertion technique (SPLIT) during oral FOB.

The opposite role of two UBA-UBX containing proteins, p47 and SAKS1 in the degradation of a single ERAD substrate, α-TCR.

The UBA-UBX domain-containing proteins can interact with ubiquitinated substrates and p97 during endoplasmic reticulum-associated degradation (ERAD). Here, we found that the expressions of all UBA-UBX genes p47, SAKS1, UBXD8, FAF1, and UBXD7 were elevated upon ER stress, albeit with different levels. Of which p47, SAKS1, and UBXD8 are 'immediate' respondents whereas FAF1 and UBXD7 were 'late' respondents to ER stress.

UbcD4, an ortholog of E2-25K/Ube2K, is essential for activation of the immune deficiency pathway in Drosophila.

Ubiquitination is a key regulatory mechanism in the immune deficiency (IMD) pathway in Drosophila. In this study, we first developed a simple immunoblot method to identify components involved in this pathway. Considering the emerging roles of ubiquitin-conjugating enzymes (E2s) in determining ubiquitin chain types and ubiquitination speed, we screened for E2s required for IMD activation.

Functional differences between two major ubiquitin receptors in the proteasome; S5a and hRpn13.

It is well known that S5a and hRpn13 are two major ubiquitin (Ub) receptors in the proteasome but little is known about their functional difference in recruiting ubiquitinated substrates. In this study using siRNA-mediated knockdown of S5a or hRpn13, we found that two Ub receptors had different substrate specificity although similar level of accumulation of high molecular weight Ub-conjugates was observed. Interesting enough, depletion of S5a, but not hRpn13, resulted in the Ub-containing aggregates and induced ER chaperones such as Grp78 and Grp94.

The ubiquitin-interacting motifs of S5a as a unique upstream inhibitor of the 26S proteasome.

It has been demonstrated that ubiquitin-conjugated proteins were accumulated by ectopically-expressed S5a as well as the ubiquitin-interacting motifs of S5a (S5a-UIMs). In this study, we further found that free S5a-UIMs stabilized only a subset of proteasomal substrates including p53, c-Fos, c-Jun, and p27 but not beta-catenin, p15, and ornithine decarboxylase. Both S5a-UIMs and epoxomicin inhibited the proliferation of A549 lung cancer cells but arrest at the different stages of cell cycle.

The ubiquitin-interacting motif of 26S proteasome subunit S5a induces A549 lung cancer cell death.

The subunit S5a is a key component for the recruitment of ubiquitinated substrates to the 26S proteasome. When the full-length S5a, the N-terminal half of S5a (S5aN) containing the von Willebrand A (vWA) domain, and the C-terminal half of S5a (S5aC) containing two ubiquitin(Ub)-interacting motifs (UIMs) were ectopically expressed in HEK293 cells, Ub-conjugates accumulated most prominently in S5aC-expressing cells. In addition, S5aC induced A549 lung cancer cell death but not non-cancer BEAS-2B cell death.