TAZ-hTrap: A Rationally Designed, Disulfide-Stapled Tead Helical Hairpin Trap to Selectively Capture Hippo Signaling Taz With Potent Antigynecological Tumor Activity.

Transcriptional enhanced associate domain (Tead)-mediated Hippo signaling pathway regulates diverse physiological processes; its dysfunction has been implicated in an increasing number of human gynecological cancers. The transcriptional coactivator with PDZ-binding motif (Taz) binds to and then activates Tead through forming a three-helix bundle (THB) at their complex interface. The THB is defined by a double-helical hairpin from Tead and a single α-helix from Taz, serving as the key interaction hotspot between Tead and Taz. In the present study, the helical hairpin was derived from Tead protein to generate a hairpin segment, which is a 25-mer polypeptide consisting of a longer helical arm-1 and a shorter helical arm-2 as well as a flexible loop linker between them. Dynamics simulation and energetics characterization revealed that the hairpin peptide is intrinsically disordered when splitting from its protein context, thus incurring a large entropy penalty upon binding to Taz α-helix. A disulfide bridge was introduced across the two helical arms of hairpin peptide to obtain a strong binder termed TAZ-hTrap, which can maintain in a considerably structured, native-like conformation in unbound state, and the entropy penalty was minimized by disulfide stapling to effectively improve its affinity toward the α-helix. These computational findings can be further substantiated by circular dichroism and fluorescence polarization at molecular level, and viability assay also observed a potent cytotoxic effect on diverse human gynecological tumors at cellular level. In addition, we further demonstrated that the TAZ-hTrap has a good selectivity for its cognate Taz over other noncognate proteins that share a high conservation with the Taz α-helix.

Tang B ，Du Y ，Wang J 《-》

Computational design and experimental confirmation of a disulfide-stapled YAP helix(α1)-trap derived from TEAD4 helical hairpin to selectively capture YAP α1-helix with potent antitumor activity.

Li K ，Liu L 《-》

Erratum: Eyestalk Ablation to Increase Ovarian Maturation in Mud Crabs.

《Jove-Journal of Visualized Experiments》

Structure-based design and disulfide stapling of interfacial cyclic peptidic inhibitors from thymic stromal lymphopoietin (TSLP) receptor to competitively target TSLP.

Human thymic stromal lymphopoietin (TSLP) is a pro-inflammatory cytokine located at the top of inflammatory cascade that makes it a promising therapeutic target in allergic asthma. The cell surface receptor of TSLP is a heterodimer consisting of a TSLP receptor (TSLPR) and an interleukin-17 receptor α (IL-7Rα). The TSLPR subunit should be first added to the free TSLP to form a TSLPR/TSLP pre-complex, which further recruits the IL-7Rα subunit to obtain the final TSLPR/IL-7Rα/TSLP complex. Previous works have been focused on targeting the IL-7Rα-binding site of TSLP. Instead, we herein reported an attempt for rational design of cyclic peptidic inhibitors to competitively disrupt the TSLPR-TSLP interaction based on their complex crystal structure by integrating dynamics simulation and energetics analysis as well as experimental assays at molecular level. An interfacial peptide segment derived from the hotspots of TSLPR that cover a specific TSLP-binding site on the TSLPR interface, which is expected to natively form a U-shaped conformation recognized by TSLP and thus compete with the cognate TSLPR for TSLP. The eS4P peptide was further stapled by a disulfide bridge between different residue pairs across its two arms, thus separately resulting in its two stapled cyclic counterparts, i.e. eS4P[189-198] and eS4P[188-200] peptides. Circular dichroism characterized that the stapling can effectively constrain the peptide into a native-like U-shpared conformation in free state, thus largely minimizing the entropy penalty upon its binding to TSLP. Affinity assays revealed that the stapling can considerably improve the peptide binding potency to TSLP by 2.9-fold and 8.3-fold at molecular level. In addition, we further demonstrated that the potent eS4P[188-200] peptide has a good selectivity for its cognate TSLP over other four noncognate cytokines IL-2, IL-7, IL-13 and IL-22 that are relevant with the TSLP. In this respect, it is considered that the disulfide-stapled cyclic peptide-mediated blockade of TLSP inflammatory cascade may be a new and promising therapeutic strategy against allergic asthma.

He Q ，Wei G ，Ma X ，Feng W ，Lu X ，Li Z ... -  《-》

Nicotine enhances the stemness and tumorigenicity in intestinal stem cells via Hippo-YAP/TAZ and Notch signal pathway.

Cigarette smoking is a well-known risk factor inducing the development and progression of various diseases. Nicotine (NIC) is the major constituent of cigarette smoke. However, knowledge of the mechanism underlying the NIC-regulated stem cell functions is limited. In this study, we demonstrate that NIC increases the abundance and proliferative activity of murine intestinal stem cells (ISCs) in vivo and ex vivo. Moreover, NIC induces Yes-associated protein (YAP) /Transcriptional coactivator with PDZ-binding motif (TAZ) and Notch signaling in ISCs via α7-nicotinic acetylcholine receptor (nAchR) and protein kinase C (PKC) activation; this effect was not detected in Paneth cells. The inhibition of Notch signaling by dibenzazepine (DBZ) nullified the effects of NIC on ISCs. NIC enhances in vivo tumor formation from ISCs after loss of the tumor suppressor gene Apc, DBZ inhibited NIC-induced tumor growth. Hence, this study identifies a NIC-triggered pathway regulating the stemness and tumorigenicity of ISCs and suggests the use of DBZ as a potential therapeutic strategy for treating intestinal tumors.

Isotani R ，Igarashi M ，Miura M ，Naruse K ，Kuranami S ，Katoh M ，Nomura S ，Yamauchi T ... -  《eLife》