These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Heterogeneous distribution of xylan and lignin in tension wood G-layers of the S1+G type in several Japanese hardwoods.
    Author: Higaki A, Yoshinaga A, Takabe K.
    Journal: Tree Physiol; 2017 Dec 01; 37(12):1767-1775. PubMed ID: 29177443.
    Abstract:
    A gradual shift in the microfibril angle of gelatinous layer (G-layer) of tension wood fibres of the S1+G type has been detected via potassium permanganate (KMnO4) staining. Thus, microfibril angles in fibres of the S1+G type are different from S1+S2+G type fibres. We evaluated the microfibril orientation and presence of lignin and xylan in G-layers of tension wood fibres of the S1+G type in several Japanese hardwoods. The distribution of xylan and lignin was examined using immunoelectron microscopy with anti-xylan monoclonal antibody, ultraviolet (UV) microscopy, fluorescence microscopy after acrifravine staining and transmission electron microscopy after KMnO4 staining. In transverse sections, the outer parts of the G-layers showed ultraviolet absorption and a heterogeneous KMnO4 staining pattern, suggesting that lignin was heterogeneously distributed in the outer parts of the G-layers. The heterogeneous staining pattern was found in the G-layers of several tree species; however, the degree of staining differed between tree species. In longitudinal sections, the KMnO4-staining region in the G-layers continued parallel to the cell axis to variable lengths. The orientation of cellulose microfibrils changed gradually from a steep helix to parallel to the cell axis from the outer to inner parts of the G-layers. Xylan immunolabelling was observed in the outer part of the G-layers; in some fibres, labelling was found in the innermost parts of the G-layers. Following immunogold labelling combined with KMnO4 staining, xylan labelling was mainly found in KMnO4-stained electron-opaque regions, suggesting that lignin and xylan were heterogeneously colocalized in the outer parts of the G-layers. The rotation of cellulose microfibrils and heterogeneous distribution of xylan and lignin might be a general phenomenon in S1+G tension wood fibres.
    [Abstract] [Full Text] [Related] [New Search]