Changes in sugar composition and cellulose content during the secondary cell wall biogenesis in cotton fibers

Secondary cell wall (SCW) deposition is an important process during wood formation. Although aspartic proteases (APs) have been reported to have regulatory roles in herbaceous plants, the involvement of atypical APs in SCW deposition in trees has not been reported. In this study, we characterised the Populus trichocarpa atypical AP gene PtAP66, which is involved in wood SCW deposition. Transcriptome data from the AspWood resource showed that in the secondary xylem of P. trichocarpa, PtAP66 transcripts increased from the vascular cambium to the xylem cell expansion region and maintained high levels in the SCW formation region. Fluorescent signals from transgenic Arabidopsis plant roots and transiently transformed P. trichocarpa leaf protoplasts strongly suggested that the PtAP66-fused fluorescent protein (PtAP66-GFP or PtAP66-YFP) localised in the plasma membrane. Compared with the wild-type plants, the Cas9/gRNA-induced PtAP66 mutants exhibited reduced SCW thickness of secondary xylem fibres, as suggested by the scanning electron microscopy (SEM) data. In addition, wood composition assays revealed that the cellulose content in the mutants decreased by 4.90–5.57%. Transcription analysis further showed that a loss of PtAP66 downregulated the expression of several SCW synthesis-related genes, including cellulose and hemicellulose synthesis enzyme-encoding genes. Altogether, these findings indicate that atypical PtAP66 plays an important role in SCW deposition during wood formation.

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The flowering hormone florigen accelerates secondary cell wall biogenesis to harmonize vascular maturation with reproductive development

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1906405116 ◽

2019 ◽

Vol 116 (32) ◽

pp. 16127-16136 ◽

Cited By ~ 6

Author(s):

Akiva Shalit-Kaneh ◽

Tamar Eviatar-Ribak ◽

Guy Horev ◽

Naomi Suss ◽

Roni Aloni ◽

...

Keyword(s):

Cell Wall ◽

Secondary Cell Wall ◽

Floral Induction ◽

Radial Expansion ◽

Developmental Needs ◽

Cellular Processes ◽

Cell Wall Biogenesis ◽

Reproductive Phase ◽

Shoot System ◽

Vascular Maturation

Florigen, a proteinaceous hormone, functions as a universal long-range promoter of flowering and concurrently as a generic growth-attenuating hormone across leaf and stem meristems. In flowering plants, the transition from the vegetative phase to the reproductive phase entails the orchestration of new growth coordinates and a global redistribution of resources, signals, and mechanical loads among organs. However, the ultimate cellular processes governing the adaptation of the shoot system to reproduction remain unknown. We hypothesized that if the mechanism for floral induction is universal, then the cellular metabolic mechanisms underlying the conditioning of the shoot system for reproduction would also be universal and may be best regulated by florigen itself. To understand the cellular basis for the vegetative functions of florigen, we explored the radial expansion of tomato stems. RNA-Seq and complementary genetic and histological studies revealed that florigen of endogenous, mobile, or induced origins accelerates the transcription network navigating secondary cell wall biogenesis as a unit, promoting vascular maturation and thereby adapting the shoot system to the developmental needs of the ensuing reproductive phase it had originally set into motion. We then demonstrated that a remarkably stable and broadly distributed florigen promotes MADS and MIF genes, which in turn regulate the rate of vascular maturation and radial expansion of stems irrespective of flowering or florigen level. The dual acceleration of flowering and vascular maturation by florigen provides a paradigm for coordinated regulation of independent global developmental programs.

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Changes in the cell wall and cellulose content of developing cotton fibers investigated by FTIR spectroscopy

Carbohydrate Polymers ◽

10.1016/j.carbpol.2013.01.074 ◽

2014 ◽

Vol 100 ◽

pp. 9-16 ◽

Cited By ~ 208

Author(s):

Noureddine Abidi ◽

Luis Cabrales ◽

Candace H. Haigler

Keyword(s):

Cell Wall ◽

Ftir Spectroscopy ◽

Cotton Fibers ◽

Cellulose Content

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Strength and Crystalline Structure of Developing Acala Cotton

Textile Research Journal ◽

10.1177/004051759706700708 ◽

1997 ◽

Vol 67 (7) ◽

pp. 529-536 ◽

Cited By ~ 28

Author(s):

Y.-L. Hsieh ◽

X.-P. Hu ◽

A. Nguyen

Keyword(s):

Cell Wall ◽

Secondary Cell Wall ◽

Fiber Development ◽

Single Fiber ◽

Cotton Fibers ◽

Cellulose Biosynthesis ◽

Cellulose I ◽

Peak Intensity ◽

Crystallite Sizes ◽

Fiber Breaking

Single fiber strengths and crystalline structures of greenhouse-grown Maxxa Acala cotton fibers at varying stages of development and at maturity are reported and compared with those of SJ-2 cotton fibers. Single fiber breaking forces of the Maxxa variety increase most significantly during the fourth week of fiber development; these increases correlate to the 60 to 90 mg seed fiber weight range. The forces required to break single fibers are similar for the SJ-2 and Maxxa varieties through the end of the fourth week of development. Beyond 30 dpa, both single fiber breaking forces and tenacities of the Maxxa cotton fibers are higher than those of the SJ-2 cotton fibers. Four waxd peaks located near 2θ angles of 14.7, 16.6, 22.7, and 34.4° are characteristic of the 101, 101, 002, and 040 reflections of cellulose I, respectively. The 002 peak intensity increases greatly during cellulose biosynthesis, indicating improved alignment of the glucosidic rings and improved order of atoms located within the glucosidic rings as the secondary cell wall thickens. The overall crystallinity and apparent crystallite sizes normal to the 101, 101, and 002 planes increase with fiber development for both varieties. Within each variety, the single fiber breaking forces are positively related to both the overall crystallinity and crystallite sizes. Between these two varieties, increasing breaking forces and tenacities appear to be related more to crystallite size than to crystallinity.

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Golgi-localized GALT7 and GALT8 participate in cellulose biosynthesis

10.1101/2021.04.21.440809 ◽

2021 ◽

Author(s):

Pieter Nibbering ◽

Romain Castilleux ◽

Gunnar Wingsle ◽

Totte Niittylä

Keyword(s):

Cell Wall ◽

Golgi Apparatus ◽

Secondary Cell Wall ◽

Plant Cell Wall ◽

Arabinogalactan Protein ◽

Primary Cell Wall ◽

Cellulose Content ◽

Cellulose Biosynthesis ◽

Cell Wall Assembly ◽

Protein Levels

AbstractArabinogalactan protein (AGP) glycan biosynthesis in the Golgi apparatus contributes to plant cell wall assembly, but the mechanisms underlying this process are largely unknown. Here, we show that two putative galactosyltransferases -named GALT7 and GALT8 -from the glycosyltransferase family 31 (GT31) of Arabidopsis thaliana participate in cellulose biosynthesis. galt7galt8 mutants show primary cell wall defects manifesting as impaired growth and cell expansion in seedlings and etiolated hypocotyls, along with secondary cell wall defects, apparent as collapsed xylem vessels and reduced xylem wall thickness in the inflorescence stem. These phenotypes were associated with a ∼30% reduction in cellulose content, a ∼50% reduction in secondary cell wall CELLULOSE SYNTHASE (CESA) protein levels and reduced cellulose biosynthesis rate. CESA transcript levels were not significantly altered in galt7galt8 mutants, suggesting that the reduction in CESA levels was caused by a post-transcriptional mechanism. We provide evidence that both GALT7 and GALT8 localise to the Golgi apparatus, while quantitative proteomics experiments revealed reduced levels of the entire FLA subgroup B in the galt7galt8 mutants. This leads us to hypothesize that a defect in FLA subgroup B glycan biosynthesis reduces cellulose biosynthesis rate in galt7galt8 mutants.

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Organized Cell Wall Biogenesis in Oocystis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050457 ◽

1974 ◽

Vol 32 ◽

pp. 88-89

Author(s):

David Montezinos ◽

R. Malcolm Brown

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Secondary Cell Wall ◽

Cell Wall Biogenesis ◽

Complex Process

Patterned arrays of cellulosic microfibrils are found in the secondary cell wall of Oocystis apiculata W. West. Although mechanisms for the biogenesis of the organized cell wall have not yet ben elucidated, roles for the plasma membrane and microtubules in wall production have been suggested. Continuing Study of Oocystis has provided new data on the complex process of organized cell wall biogenesis.

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