Emerging evidences exhibit that mitogen-activated protein kinase (MAPK/MPK) signaling pathways are connected with many aspects of plant development. The complexity of MAPK cascades raises challenges not only to identify the MAPK module in planta but also to define the specific role of an individual module. So far, our knowledge of MAPK signaling has been largely restricted to a small subset of MAPK cascades. Our previous study has characterized an Arabidopsis bushy and dwarf1 (bud1) mutant, in which the MAP Kinase Kinase 7 (MKK7) was constitutively activated, resulting in multiple phenotypic alterations. In this study, we found that MPK3 and MPK6 are the substrates for phosphorylation by MKK7 in planta. Genetic analysis showed that MKK7-MPK6 cascade is specifically responsible for the regulation of shoot branching, hypocotyl gravitropism, filament elongation, and lateral root formation, while MKK7-MPK3 cascade is mainly involved in leaf morphology. We further demonstrated that the MKK7-MPK6 cascade controls shoot branching by phosphorylating Ser 337 on PIN1, which affects the basal localization of PIN1 in xylem parenchyma cells and polar auxin transport in the primary stem. Our results not only specify the functions of the MKK7-MPK6 cascade but also reveal a novel mechanism for PIN1 phosphorylation, establishing a molecular link between the MAPK cascade and auxin-regulated plant development.

Signaling mediated by cell surface receptor kinases is central to the coordination of growth patterns during organogenesis. Receptor kinase signaling is in part controlled through endocytosis and subcellular distribution of the respective receptor kinase. For the majority of plant cell surface receptors, the underlying trafficking mechanisms are not characterized. In Arabidopsis, tissue morphogenesis requires the atypical receptor kinase STRUBBELIG (SUB). Here, we studied the endocytic mechanism of SUB. Our data revealed that a functional SUB–enhanced green fluorescent protein (EGFP) fusion is ubiquitinated in vivo. We further showed that plasma membrane-bound SUB:EGFP becomes internalized in a clathrin-dependent fashion. We also found that SUB:EGFP associates with the trans-Golgi network and accumulates in multivesicular bodies and the vacuole. Co-immunoprecipitation experiments revealed that SUB:EGFP and clathrin are present within the same protein complex. Our genetic analysis showed that SUB and CLATHRIN HEAVY CHAIN (CHC) 2 regulate root hair patterning. By contrast, genetic reduction of CHC activity ameliorates the floral defects of sub mutants. Taken together, the data indicate that SUB undergoes clathrin-mediated endocytosis, that this process does not rely on stimulation of SUB signaling by an exogenous agent, and that SUB genetically interacts with clathrin-dependent pathways in a tissue-specific manner.

23 24 Short title: SUB mediates cell wall stress signaling 25 26 Abstract 29 Plant cells are encased in a semi-rigid cell wall of complex build. As a consequence, 30 cell wall remodeling is essential for the control of growth and development as well as 31 the regulation of abiotic and biotic stress responses. Plant cells actively sense physico-32 chemical changes in the cell wall and initiate corresponding cellular responses. 33 However, the underlying cell wall monitoring mechanisms remain poorly understood.34 In Arabidopsis the atypical receptor kinase STRUBBELIG (SUB) mediates tissue 35 morphogenesis. Here, we show that SUB-mediated signal transduction also regulates 36 the cellular response to a reduction in the biosynthesis of cellulose, a central 37 carbohydrate component of the cell wall. SUB signaling affects early increase of 38 intracellular reactive oxygen species, stress gene induction as well as ectopic lignin 39 and callose accumulation upon exogenous application of the cellulose biosynthesis 40 inhibitor isoxaben. Moreover, our data reveal that SUB signaling is required for 41 maintaining cell size and shape of root epidermal cells and the recovery of root 42 growth after transient exposure to isoxaben. SUB is also required for root growth 43 arrest in mutants with defective cellulose biosynthesis. Genetic data further indicate 44 that SUB controls the isoxaben-induced cell wall stress response independently from 45 other known receptor kinase genes mediating this response, such as THESEUS1 or 46 MIK2. We propose that SUB functions in a least two distinct biological processes: the 47 control of tissue morphogenesis and the response to cell wall damage. Taken together, 48 our results reveal a novel signal transduction pathway that contributes to the 49 molecular framework underlying cell wall integrity signaling. 50 51 52 3 53 Author Summary54 Plant cells are encapsulated by a semi-rigid and biochemically complex cell wall. This 55 particular feature has consequences for multiple biologically important processes, 56 such as cell and organ growth or various stress responses. For a plant cell to grow the 57 cell wall has to be modified to allow cell expansion, which is driven by outward-58 directed turgor pressure generated inside the cell. In return, changes in cell wall 59 architecture need to be monitored by individual cells, and to be coordinated across 60 cells in a growing tissue, for an organ to attain its regular size and shape. Cell wall 61 surveillance also comes also into play in the reaction against certain stresses, 62 including for example infection by plant pathogens, many of which break through the 63 cell wall during infection, thereby generating wall-derived factors that can induce 64 defense responses. There is only limited knowledge regarding the molecular system 65 that monitors the composition and status of the cell wall. Here we provide further 66 insight into the mechanism. We show that the cell surface receptor STRUBBELIG, 67 previously known to control organ development in Ar...

Plant cells are encased in a semi-rigid cell wall of complex build. As a consequence, cell wall remodeling is essential for the control of growth and development as well as the regulation of abiotic and biotic stress responses. Plant cells actively sense physico-chemical changes in the cell wall and initiate corresponding cellular responses. However, the underlying cell wall monitoring mechanisms remain poorly understood. In Arabidopsis the atypical receptor kinase STRUBBELIG (SUB) mediates tissue morphogenesis. Here, we show that SUBmediated signal transduction also regulates the cellular response to a reduction in the biosynthesis of cellulose, a central carbohydrate component of the cell wall. SUB signaling affects early increase of intracellular reactive oxygen species, stress gene induction as well as ectopic lignin and callose accumulation upon exogenous application of the cellulose biosynthesis inhibitor isoxaben. Moreover, our data reveal that SUB signaling is required for maintaining cell size and shape of root epidermal cells and the recovery of root growth after transient exposure to isoxaben. SUB is also required for root growth arrest in mutants with defective cellulose biosynthesis. Genetic data further indicate that SUB controls the isoxaben-induced cell wall stress response independently from other known receptor kinase genes mediating this response, such as THESEUS1 or MIK2. We propose that SUB functions in a least two distinct biological processes: the control of tissue morphogenesis and the response to cell wall damage. Taken together, our results reveal a novel signal transduction pathway that contributes to the molecular framework underlying cell wall integrity signaling.

In this study, we prepared a kind of novel microecologics, namely Chinese medicine–probiotic compound microecological preparation ( CPCMP ), which is composed of 5 traditional Chinese medicine herbs ( Galla Chinensis, Andrographis paniculata, Arctii Fructus, Glycyrrhizae Radix , and Schizonepeta tenuifolia ) fermented by Aspergillus niger and a kind of compound probiotics ( Lactobacillus plantarum A37 and L. plantarum MIII). The effects of the CPCMP in broilers on growth performance, serum parameters, immune function, and intestinal health were investigated. A total of 450 one-day-old male Arbor Acres broilers were randomly divided into 6 treatment groups with 5 replicates, 15 birds per replicate. Treatments consisted of: blank control, CPCMP, positive control, commercial CPCMP, traditional Chinese medicine, and probiotics groups, which were birds fed with basal diet supplemented with no extra additives, 0.2% CPCMP, 0.0035% chlortetracycline, 0.2% commercially available CPCMP, 0.2% fermented traditional Chinese medicines, and 0.2% compound probiotics, respectively. CPCMP obviously increased the average body weight and average daily gain ( P < 0.05, compared with any other group) and decreased the feed:gain ratio of broilers ( P < 0.05, compared with the blank control, commercial CPCMP, traditional Chinese medicine, or probiotics group). Moreover, it significantly increased glutathione peroxidase and secretory immunoglobulin A levels and spleen/bursa indices ( P < 0.05 for all, compared with the blank control, commercial CPCMP, traditional Chinese medicine, or probiotics group). Villus heights in duodenum, jejunum, and ileum were also elevated by CPCMP treatment ( P < 0.05, compared with any other group). Furthermore, CPCMP substantially increased jejunal mRNA levels of occludin and zonula occludens-1 ( P < 0.05, compared with the blank control, positive control, or probiotics group) and facilitated the growth and colonization of beneficial cecal bacteria, such as Olsenella, Barnesiella , and Lactobacillus . Overall results show that the CPCMP prepared in our work contributes to improving growth performance, serum parameters, immune function, and intestinal health of broilers and exerts synergistic effects of traditional Chinese medicines and probiotics to some extent. Our findings suggest that CPCMP is a promising antibiotic substitute in the livestock and poultry industry in the future.

The mitogenome of Brentisentisyangtzensis is 13,864 bp in length and has the circular structure typical of metazoans. It contains 36 genes: 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and 12 protein-encoding genes (PCGs). All genes are transcribed from the same strand. Thirteen overlapping regions were found in the mitochondrial genome. The overall A+T content of B.yangtzensis is 68.3% versus 31.7% of G+C content (A = 27.8%, T = 40.5%, C = 9.0%, G = 22.7%). B.yangtzenensis (Illiosentidae) and Leptorhynchoidesthecatus (Rhadinorhynchidae) form a sister clade, showing the relatively close relationship between the Illiosentidae and the Rhadinorhynchidae. The mitochondrial gene arrangements of acanthocephalan species are relatively conserved, with only a few translocations of tRNAs (trnS1, trnS2, trnV, and trnK) detected. An identical gene order was found both in a sister clade (Centrorhynchusaluconis and Plagiorhynchustransversus) and across different classes (B.yangtzensis (Palaeacanthocephala), Acanthosentischeni (Eoacanthocephala) and Macracanthorhynchushirudinaceus (Archiacanthocephala), Oncicolaluehei and L.thecatus (Palaeacanthocephala)). More studies and more sequences of acanthocephalan species are needed to gain a clear understanding of the phylogenetic relationships.

In the present study, the complete sequence of the mitochondrial genome (mitogenome) of Daphnis nerii (Lepidoptera: Sphingidae) is described. The mitogenome (15,247 bp) of D.nerii encodes13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and an adenine (A) + thymine (T)-rich region. Its gene complement and order is similar to that of other sequenced lepidopterans. The 12 PCGs initiated by ATN codons except for cytochrome c oxidase subunit 1 (cox1) gene that is seemingly initiated by the CGA codon as documented in other insect mitogenomes. Four of the 13 PCGs have the incomplete termination codon T, while the remainder terminated with the canonical stop codon. This mitogenome has six major intergenic spacers, with the exception of A+T-rich region, spanning at least 10 bp. The A+T-rich region is 351 bp long, and contains some conserved regions, including ‘ATAGA’ motif followed by a 17 bp poly-T stretch, a microsatellite-like element (AT)9 and also a poly-A element. Phylogenetic analyses based on 13 PCGs using maximum likelihood (ML) and Bayesian inference (BI) revealed that D. nerii resides in the Sphingidae family.

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