TY  - JOUR
A1  - Muntaha, Sidratul Nur
A1  - Li, Xiaoping
A1  - Compart, Julia
A1  - Apriyanto, Ardha
A1  - Fettke, Jörg
T1  - Carbon pathways during transitory starch degradation in Arabidopsis differentially affect the starch granule number and morphology in the dpe2/phs1 mutant background
JF  - Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology
N2  - The Arabidopsis knockout mutant lacking both the cytosolic disproportionating enzyme 2 (DPE2) and the plastidial phosphorylase (PHS1) had a dwarf-growth phenotype, a reduced and uneven distribution of starch within the plant rosettes, and a lower starch granule number per chloroplast under standard growth conditions. In contrast, a triple mutant impaired in starch degradation by its additional lack of the glucan, water dikinase (GWD) showed improved plant growth, a starch-excess phenotype, and a homogeneous starch distribution. Furthermore, the number of starch granules per chloroplast was increased and was similar to the wild type. We concluded that ongoing starch degradation is mainly responsible for the observed phenotype of dpe2/phs1. Next, we generated two further triple mutants lacking either the phosphoglucan, water dikinase (PWD), or the disproportionating enzyme 1 (DPE1) in the background of the double mutant. Analysis of the starch metabolism revealed that even minor ongoing starch degradation observed in dpe2/phs1/pwd maintained the double mutant phenotype. In contrast, an additional blockage in the glucose pathway of starch breakdown, as in dpe2/phs1/ dpe1, resulted in a nearly starch-free phenotype and massive chloroplast degradation. The characterized mutants were discussed in the context of starch granule formation.
KW  - Starch granules
KW  - Starch metabolism
KW  - Starch granule number per
KW  - chloroplast
KW  - Starch morphology
KW  - LCSM
KW  - Arabidopsis thaliana
Y1  - 2022
U6  - https://doi.org/10.1016/j.plaphy.2022.03.033
SN  - 0981-9428
SN  - 1873-2690
VL  - 180
SP  - 35
EP  - 41
PB  - Elsevier
CY  - Paris
ER  -