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Mitogen-activated protein kinase (MAPK) cascades support the flow of extracellular signals to intracellular target molecules and ultimately drive a diverse array of physiological functions in cells, tissues, and organisms by interacting with other proteins. Yet, our knowledge of the global physical MAPK interactome in plants remains largely fragmented. Here, we utilized the yeast twohybrid system and coimmunoprecipitation, pull-down, bimolecular fluorescence complementation, subcellular localization, and kinase assay experiments in the model crop rice (Oryza sativa) to systematically map what is to our knowledge the first plant MAPK-interacting proteins. We identified 80 nonredundant interacting protein pairs (74 nonredundant interactors) for rice MAPKs and elucidated the novel proteome-wide network of MAPK interactors. The established interactome contains four membrane-associated proteins, seven MAP2Ks (for MAPK kinase), four MAPKs, and 59 putative substrates, including 18 transcription factors. Several interactors were also validated by experimental approaches (in vivo and in vitro) and literature survey. Our results highlight the importance of OsMPK1, an ortholog of tobacco (Nicotiana benthamiana) salicyclic acid-induced protein kinase and Arabidopsis (Arabidopsis thaliana) AtMPK6, among the rice MAPKs, as it alone interacts with 41 unique proteins (51.2% of the mapped MAPK interaction network). Additionally, Gene Ontology classification of interacting proteins into 34 functional categories suggested MAPK participation in diverse physiological functions. Together, the results obtained essentially enhance our knowledge of the MAPK-interacting protein network and provide a valuable research resource for developing a nearly complete map of the rice MAPK interactome.

This study suggests an integrative transfer of training model and examines the influence of pre-training performance on the relationship between work environment variables and transfer-related variables. Structural equation modeling was conducted with data collected from 365 Korean employees of a large general insurance firm. They were all participants in a leadership development program. The results of multi-group analyses revealed that the influence of work environment variables on transfer-related variables was moderated by employees' pre-training performance. The findings of the study imply that a more elaborate training transfer model that considers performance not just as an outcome variable, but also as an antecedent variable is required. Also, it is proposed that different strategies should be applied to promote transfer of training based on the employee's level of pre-training performance.

Social-networking sites (SNSs) provide users with a unique computer-mediated environment where individuals are able to disclose their thoughts, feelings, and experiences within their circle of personal ties. From a positive psychological perspective, this research investigated the use of SNSs and users' subjective well-being. The results show that although the time spent using a SNS is not related to well-being, the amount of self-disclosure on SNSs is positively related to subjective well-being. In addition, an individual's socioeconomic status is negatively related to self-disclosing behavior.

Secreted proteins control a multitude of biological and physiological processes in multicellular organisms such as plants. Identification of secreted proteins in reference plants like Arabidopsis and rice under normal growth conditions and adverse environmental conditions will help better understand the secretory pathways. Here, we have performed a systematic in planta and in vitro analyses of proteins secreted by rice leaves (in planta) and seed callus suspension-cultured cells (SCCs; in vitro), respectively, using a combination of biochemical and two-dimensional gel electrophoresis (2-DGE) coupled with liquid chromatography mass spectrometry analyses. Secreted proteins prepared from either leaves or SCCs medium were essentially free from contamination of intracellular proteins as judged by biochemical and Western blot analyses. 2-DGE analyses of secreted proteins collectively identified 222 protein spots with only 6 protein spots common to both in planta and in vitro derived data sets. Data were used to establish high-resolution and high-density 2-D gel reference maps for both in planta and in vitro secreted proteins. Identified proteins belonged to 11 (in planta) and 6 (in vitro) functional classes. Proteins involved in carbon metabolism (33%) and cell wall metabolism having plant defense mechanism (18%) were highly represented in the in planta secreted proteins accounting for 51% of total identified proteins, whereas proteins of cell wall metabolism having plant defense mechanism (64%) were predominant in the in vitro secreted proteins. Interestingly, secreted proteins possessing signal peptides were significantly lower in an in planta (27%) prepared secreted protein population than in vitro (76%) as predicted by SignalP prediction tool, implying the notion that plant might possess yet unidentified secretory pathway(s) in addition to the classical endoplasmic reticulum/Golgi pathway. Taken together, this systematic study provides evidence for (i) significant difference in protein population secreted in planta and in vitro suggesting both approaches are complementary, (ii) identification of many novel and previously known secreted proteins, and (iii) the presence of large number of functionally diverse proteins secreted in planta and in vitro.

The human lysyl oxidase-like 3 (LOXL3) encodes a member of the emerging family of lysyl oxidase (LOX) that functions as a copper-dependent amine oxidase. The LOXL3 protein contains four scavenger receptor cysteine-rich domains in the N terminus in addition to the C-terminal characteristic domains of the LOX family, such as a copper binding domain, a cytokine receptor-like domain and residues for the lysyl-tyrosyl quinone cofactor. Using BLASTN searches, we identified a LOXL3 variant LOXL3-sv1 that lacked the sequences corresponding to exons 1, 2, 3, and 5 of LOXL3. LOXL3-sv1 showed an exon-intron structure distinct from LOXL3, additionally containing an 80-bp sequence corresponding to intron 3 of LOXL3 in the 5 -UTR and a 561-bp sequence corresponding to the 3 -flanking genomic region of exon 14 in the 3 -UTR. LOXL3-sv1 was predicted to encode a polypeptide of 392 amino acids that contains the C-terminal domains required for amine oxidase activity but lacks the N-terminal SRCR domains 1, 2, and 3. The recombinant LOXL3-sv1 protein showed a ␤-aminopropionitrile-inhibitable amine oxidase activity toward elastin and collagen with substrate specificity. In RT-PCR assays with various human tissues, LOXL3-sv1 and LOXL3 showed distinct expression patterns. Further, luciferase reporter assays revealed a strong promoter element in intron 3 that probably functions as a regulatory region for the expression of LOXL3-sv1. These findings strongly indicate that LOXL3 encodes two variants, LOXL3 and LOXL3-sv1, both of which function as amine oxidases with distinct tissue and substrate specificities from one another.Lysyl oxidase (LOX), 2 a copper-dependent amine oxidase, is responsible for the development of lysine-derived cross-links in extracellular matrix proteins, such as collagen and elastin (1). LOX oxidizes the epsilon amino groups of peptidyl lysines to reactive aldehydes. The resulting aldehyde groups then undergo spontaneous condensation with unreacted epsilon amino groups or neighboring aldehyde groups, converting collagen or elastin monomers into insoluble fibers (2, 3). The LOX-mediated cross-linkage of collagen or elastin monomers is an essential step for the biogenesis of fibrillar extracellular matrix in most tissues.Recent molecular cloning has revealed the existence of a human LOX family consisting of the five paralogues LOX, LOXL, LOXL2, LOXL3, and LOXL4 (4 -8). Each LOX paralogue contains a copper-binding domain, residues for lysyl-tyrosyl quinone (LTQ) and a cytokine receptor-like (CRL) domain in the carboxyl (C) termini. The amino (N)-terminal regions of the LOX family members, in contrast, show little sequence homology except that LOXL2, LOXL3, and LOXL4 contain four repeated copies of scavenger receptor cysteinerich (SRCR) domains in their N termini. The SRCR domains, known to mediate the protein-protein interactions for cell adhesion and cell signaling, are found either on the cell surface proteins or secreted proteins (9, 10). The presence of SRCR domains within LOXL2, LOXL3, and LOXL4 indicates that t...

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