The AGCVIII kinase Dw2 modulates cell proliferation, endomembrane trafficking, and MLG/xylan cell wall localization in elongating stem internodes of Sorghum bicolor

Cell walls are basically complex with dynamic structures that are being involved in several growth and developmental processes, as well as responses to environmental stresses and the defense mechanism. Pectin is secreted into the cell wall in a highly methylesterified form. It is able to perform function after the de-methylesterification by pectin methylesterase (PME). Whereas, the pectin methylesterase inhibitor (PMEI) plays a key role in plant cell wall modification through inhibiting the PME activity. It provides pectin with different levels of degree of methylesterification to affect the cell wall structures and properties. The PME activity was analyzed in six tissues of Sorghum bicolor, and found a high level in the leaf and leaf sheath. PMEI families have been identified in many plant species. Here, a total of 55 pectin methylesterase inhibitor genes (PMEIs) were identified from S. bicolor whole genome, a more detailed annotation of this crop plant as compared to the previous study. Chromosomal localization, gene structures and sequence characterization of the PMEI family were analyzed. Moreover, cis-acting elements analysis revealed that each PMEI gene was regulated by both internal and environmental factors. The expression patterns of each PMEI gene were also clustered according to expression pattern analyzed in 47 tissues under different developmental stages. Furthermore, some SbPMEIs were induced when treated with hormonal and abiotic stress. Taken together, these results laid a strong foundation for further study of the functions of SbPMEIs and pectin modification during plant growth and stress responses of cereal.

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Ultrastructure of the Infection of Sorghum bicolor by Colletotrichum sublineolum

Phytopathology ◽

10.1094/phyto.2001.91.2.149 ◽

2001 ◽

Vol 91 (2) ◽

pp. 149-158 ◽

Cited By ~ 67

Author(s):

P. S. Wharton ◽

A. M. Julian ◽

R. J. O'Connell

Keyword(s):

Cell Wall ◽

Sorghum Bicolor ◽

Epidermal Cells ◽

Host Cells ◽

Wall Thickening ◽

Fungal Cell ◽

Resistant Cultivars ◽

Ultrastructural Studies ◽

Opaque Material ◽

Colletotrichum Sublineolum

Ultrastructural studies of the infection of susceptible and resistant cultivars of Sorghum bicolor by Colletotrichum sublineolum were conducted. Initial penetration events were the same on both susceptible and resistant cultivars. Germ tubes originating from germinated conidia formed globose, melanized appressoria, that penetrated host epidermal cells directly. Appressoria did not produce appressorial cones, but each penetration pore was surrounded by an annular wall thickening. Inward deformation of the cuticle and localized changes in staining properties of the host cell wall around the infection peg suggests that penetration involves both mechanical force and enzymic dissolution. In compatible interactions, penetration was followed by formation of biotrophic globular infection vesicles in epidermal cells. Filamentous primary hyphae developed from the vesicles and went on to colonize many other host cells as an intracellular mycelium. Host cells initially survived penetration. The host plasma membrane invaginated around infection vesicles and primary hyphae and was appressed tightly to the fungal cell wall, with no detectable matrix layer at the interface. Necrotrophic secondary hyphae appeared after 66 h and ramified through host tissue both intercellularly and intracellularly, forming hypostromatic acervuli by 114 h. Production of secondary hyphae was accompanied by the appearance of electron-opaque material within infected cells. This was thought to represent the host phytoalexin response. In incompatible interactions, infection vesicles and primary hyphae were formed in epidermal cells by 42 h. However, they were encrusted with electron-opaque material and appeared dead. These observations are discussed in relation to the infection processes of other Colletotrichum spp. and the host phytoalexin response.

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Conjugation of resting nuclei in an epithelioma of the mouse.

Proceedings of the Royal Society of London ◽

10.1098/rspl.1904.0011 ◽

1904 ◽

Vol 73 (488-496) ◽

pp. 77-77 ◽

Cited By ~ 1

Author(s):

E. F. Bashford ◽

James Alexander Murray ◽

John Rose Bradford

Keyword(s):

Cell Proliferation ◽

Cell Wall ◽

Outer Surface ◽

Previous Communication

In a previous communication we have drawn attention to the fact that the power of cell proliferation, which has been proved to occur in an epithelioma of the mouse (Jensen), is a phenomenon unparalleled in the mammalia. A mass of tumour, 16 lbs. in weight, has been produced by artificially transplanting portions of the original growth and its descendants. In seeking to throw light on this fact, we have studied carefully the phenomena which follow the transplantations of portions of the tissue to new sites, and have found that the tumours which arise are the genealogical descendants of the cells introduced. We have studied the growth of the tumours which arise at successive stages of 24 hours. In a tumour removed on the eighth day, and less than half a split pea in size, conjugation of resting nuclei has been observed. To take a specific case, the nuclei of two adjacent cells are continuous through the cell wall by a tube-like bridge, in the middle of which a strand of nucleolar substance with fusiform swellings in either cell is visible. The cells of this particular case are adjacent to. the stroma, and close to the outer surface of the young tumour.

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Host-parasite tissue adhesion by a secreted type of β-1,4-glucanase in the parasitic plant Phtheirospermum japonicum

10.1101/2020.03.29.014886 ◽

2020 ◽

Author(s):

Ken-ichi Kurotani ◽

Takanori Wakatake ◽

Yasunori Ichihashi ◽

Koji Okayasu ◽

Yu Sawai ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Wall ◽

Plant Species ◽

Parasitic Infection ◽

Parasitic Plants ◽

Parasitic Plant ◽

Striga Hermonthica ◽

Gene Clustering ◽

Cell Wall Modification ◽

Tissue Adhesion

AbstractTissue adhesion between plant species occurs both naturally and artificially. Parasitic plants establish symbiotic relationship with host plants by adhering tissues at roots or stems. Plant grafting, on the other hand, is a widely used technique in agriculture to adhere tissues of two stems. While compatibility of tissue adhesion in plant grafting is often limited within close relatives, parasitic plants exhibit much wider compatibilities. For example, the Orobanchaceae parasitic plant Striga hermonthica is able to infect Poaceae crop plants, causing a serious agricultural loss. Here we found that the model Orobanchaceae parasite plant Phtheirospermum japonicum can be grafted on to interfamily species, such as Arabidopsis, a Brassicaceae plant. To understand molecular basis of tissue adhesion between distant plant species, we conducted comparative transcriptome analyses on both infection and grafting by P. japonicum on Arabidopsis. Through gene clustering, we identified genes upregulated during these tissue adhesion processes, which include cell proliferation- and cell wall modification-related genes. By comparing with a transcriptome dataset of interfamily grafting between Nicotiana and Arabidopsis, we identified 9 genes commonly induced in tissue adhesion between distant species. Among them, we showed a gene encoding secreted type of β-1,4-glucanase plays an important role for plant parasitism. Our data provide insights into the molecular commonality between parasitism and grafting in plants.Significance StatementComprehensive sequential RNA-Seq datasets for parasitic infection of the root and grafting of the stem between P. japonicum and Arabidopsis revealed that molecular events of parasitism and grafting are substantially different and only share a part of events such as cell proliferation and cell wall modification. This study demonstrated that a secreted type of β-1,4-glucanase gene expressed in cells located at the parasite–host interface as an important factor for parasitism in the Orobanchaceae.

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An In Silico Study for the Identification of Novel Putative Compounds Against the Wild and Mutant Type Penicillin Binding Protein 2 of Neisseria Gonorrhoeae

Biointerface Research in Applied Chemistry ◽

10.33263/briac112.89969006 ◽

2020 ◽

Vol 11 (2) ◽

pp. 8996-9006

Keyword(s):

Cell Proliferation ◽

Cell Wall ◽

Hot Spots ◽

Structural Changes ◽

Binding Protein ◽

Cell Wall Biosynthesis ◽

The Novel ◽

Penicillin Binding Protein ◽

Mutant Type ◽

In Silico Study

Penicillin-binding protein 2 (PBP2) is an enzyme crucial for cell wall biosynthesis during cell proliferation of N. gonorrhoeae. In the present work, the crystal structures of wild and mutant type PBP2 were analyzed to identify structural changes leading to antibiotic resistance. Other than these two targets, three other targets were generated by analyzing possible hot spots for mutations in PBP2. By using a reverse screening approach, fifteen molecules were screened and processed for ligand binding analysis with all five targets. The analysis of the above studies suggested that two compounds Guanosine 5’-diphosphate and Thymidine 3', 5’-diphosphate show the good binding affinity than Ceftriaxone and other compounds. Further, we have generated ten novel compounds using Ceftriaxone, Guanosine 5’-diphosphate, and Thymidine 3', 5’-diphosphate. To identify the novel findings, all novel compounds were docked against aforesaid five targets. The studies resulted in the finding of three best molecules that may be considered as suitable, potent, and generic inhibitors against N. gonorrhoeae other than Ceftriaxone.

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Overexpression of the rice BAHD acyltransferase AT10 increases xylan-bound p-coumarate and reduces lignin in Sorghum bicolor

Biotechnology for Biofuels ◽

10.1186/s13068-021-02068-9 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Yang Tian ◽

Chien-Yuan Lin ◽

Joon-Hyun Park ◽

Chuan-Yin Wu ◽

Ramu Kakumanu ◽

...

Keyword(s):

Cell Wall ◽

Sorghum Bicolor ◽

Cell Walls ◽

Lignin Content ◽

Complex Structure ◽

Enzymatic Saccharification ◽

Cellulose Microfibrils ◽

Biomass Composition ◽

Bioenergy Crops ◽

Transgenic Lines

Abstract Background The development of bioenergy crops with reduced recalcitrance to enzymatic degradation represents an important challenge to enable the sustainable production of advanced biofuels and bioproducts. Biomass recalcitrance is partly attributed to the complex structure of plant cell walls inside which cellulose microfibrils are protected by a network of hemicellulosic xylan chains that crosslink with each other or with lignin via ferulate (FA) bridges. Overexpression of the rice acyltransferase OsAT10 is an effective bioengineering strategy to lower the amount of FA involved in the formation of cell wall crosslinks and thereby reduce cell wall recalcitrance. The annual crop sorghum represents an attractive feedstock for bioenergy purposes considering its high biomass yields and low input requirements. Although we previously validated the OsAT10 engineering approach in the perennial bioenergy crop switchgrass, the effect of OsAT10 expression on biomass composition and digestibility in sorghum remains to be explored. Results We obtained eight independent sorghum (Sorghum bicolor (L.) Moench) transgenic lines with a single copy of a construct designed for OsAT10 expression. Consistent with the proposed role of OsAT10 in acylating arabinosyl residues on xylan with p-coumarate (pCA), a higher amount of p-coumaroyl-arabinose was released from the cell walls of these lines upon hydrolysis with trifluoroacetic acid. However, no major changes were observed regarding the total amount of pCA or FA esters released from cell walls upon mild alkaline hydrolysis. Certain diferulate (diFA) isomers identified in alkaline hydrolysates were increased in some transgenic lines. The amount of the main cell wall monosaccharides glucose, xylose, and arabinose was unaffected. The transgenic lines showed reduced lignin content and their biomass released higher yields of sugars after ionic liquid pretreatment followed by enzymatic saccharification. Conclusions Expression of OsAT10 in sorghum leads to an increase of xylan-bound pCA without reducing the overall content of cell wall FA esters. Nevertheless, the amount of total cell wall pCA remains unchanged indicating that most pCA is ester-linked to lignin. Unlike other engineered plants overexpressing OsAT10 or a phylogenetically related acyltransferase with similar putative function, the improvements of biomass saccharification efficiency in sorghum OsAT10 lines are likely the result of lignin reductions rather than reductions of cell wall-bound FA. These results also suggest a relationship between xylan-bound pCA and lignification in cell walls.

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