biostudies-literatureGuevara-Rozo SNatural Sciences and Engineering Research Council of Canada282-298https://www.ebi.ac.uk/biostudies/studies/S-EPMC12676068biostudies-literatureUnknown249(1)Hemicelluloses are key chemical constituents of plant cell walls, influencing structure, strength, and interactions between cellulose and lignin. While xylan has been widely studied and shown to affect cell wall integrity, the function of mannan remains largely unexplored. To address this gap, we identified and functionally characterized putative mannan biosynthetic genes from spruce and poplar, and tested their impact on wood formation and digestibility. Bioinformatic and phylogenetic tools were employed to identify Cellulose Synthase-Like family A (CSLA) genes from spruce and poplar. These genes were then functionally validated by complementing the mannan deficient Arabidopsis csla2,3,9 triple mutants, and creating CRISPR-Cas9 knockouts and ectopic overexpression lines in poplar. Spruce The New phytologistUnraveling mannan biosynthesis in poplar and spruce: functional characterization of Cellulose Synthase-Like family A (CSLA) genes.PMC12676068RGPIN‐2024‐04385RGPIN-2024-04385Mansfield SDde Vries LEli EGuevara-Rozo SDupree PYoshimi YfalseUnraveling mannan biosynthesis in poplar and spruce: functional characterization of Cellulose Synthase-Like family A (CSLA) genes.Hemicelluloses are key chemical constituents of plant cell walls, influencing structure, strength, and interactions between cellulose and lignin. While xylan has been widely studied and shown to affect cell wall integrity, the function of mannan remains largely unexplored. To address this gap, we identified and functionally characterized putative mannan biosynthetic genes from spruce and poplar, and tested their impact on wood formation and digestibility. Bioinformatic and phylogenetic tools were employed to identify Cellulose Synthase-Like family A (CSLA) genes from spruce and poplar. These genes were then functionally validated by complementing the mannan deficient Arabidopsis csla2,3,9 triple mutants, and creating CRISPR-Cas9 knockouts and ectopic overexpression lines in poplar. Spruce 2026-01-01T00:00:00Z2026 Jan2026-06-05T21:57:23.223Z2026-05-22T03:15:45.844ZS-EPMC126760684118869210.1111/nph.70685