Generation of Bioactivity-Tailored FK506/FK520 Analogs by CRISPR Editing in Streptomyces tsukubaensis.

For a potential application of FK506 in the treatment of acute kidney failure only the FKBP12 binding capability of the compound is required, while the immunosuppressive activity via calcineurin binding is considered as a likely risk to the patients. The methoxy groups at C13 and C15 are thought to have significant influence on the immunosuppressive activity of the molecule. Consequently, FK506 analogs with different functionalities at C13 and C15 were generated by targeted CRISPR editing of the AT domains in module 7 and 8 of the biosynthetic assembly line in Streptomyces tsukubaensis.

Phenotypic screen identifies calcineurin-sparing FK506 analogs as BMP potentiators for treatment of acute kidney injury.

Acute kidney injury (AKI) is a life-threatening disease with no known curative or preventive therapies. Data from multiple animal models and human studies have linked dysregulation of bone morphogenetic protein (BMP) signaling to AKI. Small molecules that potentiate endogenous BMP signaling should have a beneficial effect in AKI.

Author Correction: CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma.

The post-genomic era has seen many advances in our understanding of cancer pathways, yet resistance and tumor heterogeneity necessitate multiple approaches to target even monogenic tumors. Here, we combine phenotypic screening with chemical genetics to identify pre-messenger RNA endonuclease cleavage and polyadenylation specificity factor 3 (CPSF3) as the target of JTE-607, a small molecule with previously unknown target. We show that CPSF3 represents a synthetic lethal node in a subset of acute myeloid leukemia (AML) and Ewing's sarcoma cancer cell lines.

A small-molecule inhibitor of C5 complement protein.

The complement pathway is an important part of the immune system, and uncontrolled activation is implicated in many diseases. The human complement component 5 protein (C5) is a validated drug target within the complement pathway, as an anti-C5 antibody (Soliris) is an approved therapy for paroxysmal nocturnal hemoglobinuria. Here, we report the identification, optimization and mechanism of action for the first small-molecule inhibitor of C5 complement protein.

Direct Interaction of Chivosazole F with Actin Elicits Cell Responses Similar to Latrunculin A but Distinct from Chondramide.

The microbial metabolite Chivosazole F has been described to affect the cytoskeleton and to inhibit actin polymerization in vitro. Applying orthogonal genomic and proteomics approaches, we now show for the first time that Chivosazole F exerts its effect by directly interacting with actin and demonstrate the cellular impact of Chivosazole F in an unbiased, genome-wide context in yeast and in mammalian cells. Furthermore, mutation-based resistance mapping identifies two SNPs located in the putative Chivosazole F binding site of actin.

SEC-TID: A Label-Free Method for Small-Molecule Target Identification.

Bioactive small molecules are an invaluable source of therapeutics and chemical probes for exploring biological pathways. Yet, significant hurdles in drug discovery often come from lacking a comprehensive view of the target(s) for both early tool molecules and even late-stage drugs. To address this challenge, a method is provided that allows for assessing the interactions of small molecules with thousands of targets without any need to modify the small molecule of interest or attach any component to a surface.

Identification and characterization of a peptidic ligand for Ras.

The development of new ligands for the oncoprotein Ras can provide tools for the study of this important signaling component or potentially serve as therapeutic agents for the treatment of Ras-associated diseases. Herein, we report a peptidic Ras ligand identified through naïve phage display. Panning a phage library with a diversity of 10(9) transormants successfully identified a peptide dodecamer that contains two internal consensus motifs and binds Ras in both the active GTP- and inactive GDP-bound conformations with low micromolar dissociation constants.

DcpS as a therapeutic target for spinal muscular atrophy.

Spinal muscular atrophy (SMA) is caused by deletion or mutation of both copies of the SMN1 gene, which produces an essential protein known as SMN. The severity of SMA is modified by variable copy number of a second gene,SMN2, which produces an mRNA that is incorrectly spliced with deletion of the last exon. We described previously the discovery of potent C5-substituted quinazolines that increase SMN2 gene expression by 2-fold.

Identification of small molecule targets on functional protein microarrays.

Small molecules, such as metabolites and hormones, interact with proteins to regulate numerous biological pathways, which are often aberrant in disease. Small molecule drugs have been successfully exploited to specifically perturb such processes and thereby, decrease and even eliminate disease progression. Although there are compelling reasons to fully characterize interactions of small molecules with all proteins from an organism for which an intended drug regimen is planned, currently available technologies are not yet up to this task.

A pooling-deconvolution strategy for biological network elucidation.

The generation of large-scale data sets is a fundamental requirement of systems biology. But despite recent advances, generation of such high-coverage data remains a major challenge. We developed a pooling-deconvolution strategy that can dramatically decrease the effort required.

Functional protein microarrays: just how functional are they?

Arrays of immobilized proteins have been developed for the discovery and characterization of protein functions ranging from molecular recognition to enzymatic activity. The success of these applications is highly dependent upon the maintenance of protein structure and function while in an immobilized state - a largely untested hypothesis. However, the immobilization of functional proteins is not without precedent.

Analyzing antibody specificity with whole proteome microarrays.

Although approximately 10,000 antibodies are available from commercial sources, antibody reagents are still unavailable for most proteins. Furthermore, new applications such as antibody arrays and monoclonal antibody therapeutics have increased the demand for more specific antibodies to reduce cross-reactivity and side effects. An array containing every protein for the relevant organism represents the ideal format for an assay to test antibody specificity, because it allows the simultaneous screening of thousands of proteins for possible cross-reactivity.