Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	Cryo-electron tomography of the onion cell wall shows bimodally oriented cellulose fibers and reticulated homogalacturonan networks.
Journal, issue, pages	Curr Biol, Vol. 32, Issue 11, Page 2375-22389.e6, Year 2022
Publish date	Jun 6, 2022
Authors	William J Nicolas / Florian Fäßler / Przemysław Dutka / Florian K M Schur / Grant Jensen / Elliot Meyerowitz /
PubMed Abstract	One hallmark of plant cells is their cell wall. They protect cells against the environment and high turgor and mediate morphogenesis through the dynamics of their mechanical and chemical properties. ...One hallmark of plant cells is their cell wall. They protect cells against the environment and high turgor and mediate morphogenesis through the dynamics of their mechanical and chemical properties. The walls are a complex polysaccharidic structure. Although their biochemical composition is well known, how the different components organize in the volume of the cell wall and interact with each other is not well understood and yet is key to the wall's mechanical properties. To investigate the ultrastructure of the plant cell wall, we imaged the walls of onion (Allium cepa) bulbs in a near-native state via cryo-focused ion beam milling (cryo-FIB milling) and cryo-electron tomography (cryo-ET). This allowed the high-resolution visualization of cellulose fibers in situ. We reveal the coexistence of dense fiber fields bathed in a reticulated matrix we termed "meshing," which is more abundant at the inner surface of the cell wall. The fibers adopted a regular bimodal angular distribution at all depths in the cell wall and bundled according to their orientation, creating layers within the cell wall. Concomitantly, employing homogalacturonan (HG)-specific enzymatic digestion, we observed changes in the meshing, suggesting that it is-at least in part-composed of HG pectins. We propose the following model for the construction of the abaxial epidermal primary cell wall: the cell deposits successive layers of cellulose fibers at -45° and +45° relative to the cell's long axis and secretes the surrounding HG-rich meshing proximal to the plasma membrane, which then migrates to more distal regions of the cell wall.
External links	Curr Biol / PubMed:35508170 / PubMed Central
Methods	EM (tomography) / EM (subtomogram averaging)
Structure data	EMDB-26564: Cryo-electron tomogram of non-treated onion cell wall from scale #6 (related to Figure 2 and 4A-C of primary citation) Method: EM (tomography) EMDB-26568: Cryo-electron tomogram of non-treated onion cell wall from scale #2 (related to Figure 5B, D-E of primary citation) Method: EM (tomography) EMDB-26569: Cryo-electron tomogram of non-treated onion cell wall from scale #8 (related to Figure 3 of primary citation) Method: EM (tomography) EMDB-26570: Cryo-electron tomogram of 38% methylesterified purified pectins (related to Figure S6H-I from primary citation) Method: EM (tomography) EMDB-26571: Subtomogram average of a non-treated cellulose fiber (related to Figure 7A of primary citation) Method: EM (subtomogram averaging) EMDB-26572: Subtomogram average of a bapta cellulose fiber (related to Figure 7B of primary citation) Method: EM (subtomogram averaging) EMDB-26573: Subtomogram average of a pectate lyase cellulose fiber (related to Figure 7C of primary citation) Method: EM (subtomogram averaging)
Source	Allium cepa (onion) Citrus (plant)