The Cryptosporidium signaling kinase CDPK5 plays an important role in male gametogenesis and parasite virulence.

The protozoan parasite Cryptosporidium is a leading cause of diarrhea in young children. The parasite's life cycle involves a coordinated and timely progression from asexual to sexual stages, leading to the formation of the transmissible oocyst. Underlying molecular signaling mechanisms orchestrating sexual development are not known.

Global mapping of the conventional secreted effector - host interactome reveals CebN interacts with nucleoporins and Rae1 to impede STAT1 nuclear translocation.

(.), the leading cause of bacterial sexually transmitted infections, employs a type III secretion system (T3SS) to translocate two classes of effectors, inclusion membrane proteins and conventional T3SS (cT3SS) effectors, into the host cell to counter host defense mechanisms. Here we employed three assays to directly evaluate secretion during infection, validating secretion for 23 cT3SS effectors.

Viral proteogenomic and expression profiling during productive replication of a skin-tropic herpesvirus in the natural host.

Efficient transmission of herpesviruses is essential for dissemination in host populations; however, little is known about the viral genes that mediate transmission, mostly due to a lack of natural virus-host model systems. Marek's disease is a devastating herpesviral disease of chickens caused by Marek's disease virus (MDV) and an excellent natural model to study skin-tropic herpesviruses and transmission. Like varicella zoster virus that causes chicken pox in humans, the only site where infectious cell-free MD virions are efficiently produced is in epithelial skin cells, a requirement for host-to-host transmission.

The alphaherpesvirus conserved pUS10 is important for natural infection and its expression is regulated by the conserved Herpesviridae protein kinase (CHPK).

Conserved Herpesviridae protein kinases (CHPK) are conserved among all members of the Herpesviridae. Herpesviruses lacking CHPK propagate in cell culture at varying degrees, depending on the virus and cell culture system. CHPK is dispensable for Marek's disease herpesvirus (MDV) replication in cell culture and experimental infection in chickens; however, CHPK-particularly its kinase activity-is essential for horizontal transmission in chickens, also known as natural infection.

Universal Sample Preparation Workflow for Plant Phosphoproteomic Profiling.

Mass spectrometry (MS)-based phosphoproteomics is a powerful tool for investigating cell signaling, yet it remains challenging to study plant phosphoproteomes due to the low yield of cell lysis and high complexity of plant lysate. Here we report a streamlined sample preparation workflow to analyze plant phosphoproteomes in a high-throughput manner. This workflow addresses the problem of low yield in the lysis step and eliminates the interferences of pigments and metabolites in plant lysate.

Universal Plant Phosphoproteomics Workflow and Its Application to Tomato Signaling in Response to Cold Stress.

Phosphorylation-mediated signaling transduction plays a crucial role in the regulation of plant defense mechanisms against environmental stresses. To address the high complexity and dynamic range of plant proteomes and phosphoproteomes, we present a universal sample preparation procedure that facilitates plant phosphoproteomic profiling. This advanced workflow significantly improves phosphopeptide identifications, enabling deep insight into plant phosphoproteomes.

Recent advances in phosphoproteomics and application to neurological diseases.

Phosphorylation has an incredible impact on the biological behavior of proteins, altering everything from intrinsic activity to cellular localization and complex formation. It is no surprise then that this post-translational modification has been the subject of intense study and that, with the advent of faster, more accurate instrumentation, the number of large-scale mass spectrometry-based phosphoproteomic studies has swelled over the past decade. Recent developments in sample preparation, phosphorylation enrichment, quantification, and data analysis strategies permit both targeted and ultra-deep phosphoproteome profiling, but challenges remain in pinpointing biologically relevant phosphorylation events.

Identification of Plant Kinase Substrates Based on Kinase Assay-Linked Phosphoproteomics.

Protein phosphorylation is one of the key events in the regulation of plant physiological responses to diverse environmental stimuli. As crucial regulators of phosphorylation, protein kinases have been linked to the control of seed germination, flowering, and stress responses. Identifying downstream substrates of kinases is important for dissecting kinase-substrate networks as well as delineating the underlying defense mechanisms in response to extracellular stimulation.

Estimating the Efficiency of Phosphopeptide Identification by Tandem Mass Spectrometry.

Mass spectrometry has played a significant role in the identification of unknown phosphoproteins and sites of phosphorylation in biological samples. Analyses of protein phosphorylation, particularly large scale phosphoproteomic experiments, have recently been enhanced by efficient enrichment, fast and accurate instrumentation, and better software, but challenges remain because of the low stoichiometry of phosphorylation and poor phosphopeptide ionization efficiency and fragmentation due to neutral loss. Phosphoproteomics has become an important dimension in systems biology studies, and it is essential to have efficient analytical tools to cover a broad range of signaling events.

Identification of Direct Kinase Substrates via Kinase Assay-Linked Phosphoproteomics.

Protein phosphorylation plays an essential role in the regulation of various cellular functions. Dysregulation of phosphorylation is implicated in the pathogenesis of certain cancers, diabetes, cardiovascular diseases, and central nervous system disorders. As a result, protein kinases have become potential drug targets for treating a wide variety of diseases.

Analytical challenges translating mass spectrometry-based phosphoproteomics from discovery to clinical applications.

Phosphoproteomics is the systematic study of one of the most common protein modifications in high throughput with the aim of providing detailed information of the control, response, and communication of biological systems in health and disease. Advances in analytical technologies and strategies, in particular the contributions of high-resolution mass spectrometers, efficient enrichments of phosphopeptides, and fast data acquisition and annotation, have catalyzed dramatic expansion of signaling landscapes in multiple systems during the past decade. While phosphoproteomics is an essential inquiry to map high-resolution signaling networks and to find relevant events among the apparently ubiquitous and widespread modifications of proteome, it presents tremendous challenges in separation sciences to translate it from discovery to clinical practice.

Quantitation of the phosphoproteome using the library-assisted extracted ion chromatogram (LAXIC) strategy.

Phosphorylation is a key posttranslational modification that regulates many signaling pathways, but quantifying changes in phosphorylation between samples can be challenging due to its low stoichiometry within cells. We have introduced a mass spectrometry-based label-free quantitation strategy termed LAXIC for the analysis of the phosphoproteome. This method uses a spiked-in synthetic peptide library designed to elute across the entire chromatogram for local normalization of phosphopeptides within complex samples.