PagHAM4a-PagSCL21 and PagHAM4b-PagTCP20 modules positively regulate cambial activity and its differentiation into secondary xylem in poplar.

ABSTRACT: Stem secondary xylem produced by cambial division and differentiation is the main source of tree biomass. Secondary xylem formation involves a complex transcriptional regulatory network; however, the underlying mechanism is still being explored. Here, we report that PagHAM4a and PagHAM4b are positive regulators of cambial differentiation into secondary xylem in hybrid poplar (Populus alba × Populus glandulosa clone 84K). Overexpression of PagHAM4a and PagHAM4b enhanced cambial activity and increased the number of secondary xylem cells in the stems of poplar. By contrast, single or double mutations of PagHAM4a and PagHAM4b generated by CRISPR/Cas9 decreased cambial activity, leading to a significant reduction of secondary xylem. Neither overexpression nor mutation of the two genes affected

SUBMITTER: Zhao P 

PROVIDER: S-EPMC11630012 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature