Arabidopsis Tyrosylprotein sulfotransferase acts in the auxin/PLETHORA pathway in regulating postembryonic maintenance of the root stem cell niche.
Recent identification of the Arabidopsis thaliana tyrosylprotein sulfotransferase (TPST) and a group of Tyr-sulfated peptides known as root meristem growth factors (RGFs) highlights the importance of protein Tyr sulfation in plant growth and development. Here, we report the action mechanism of TPST in maintenance of the root stem cell niche, which in the Arabidopsis root meristem is an area of four mitotically inactive quiescent cells plus the surrounding mitotically active stem cells. Mutation of TPST leads to defective maintenance of the root stem cell niche, decreased meristematic activity, and stunted root growth. We show that TPST expression is positively regulated by auxin and that mutation of this gene affects auxin distribution by reducing local expression levels of several PIN genes and auxin biosynthetic genes in the stem cell niche region. We also show that mutation of TPST impairs basal- and auxin-induced expression of the PLETHORA (PLT) stem cell transcription factor genes and that overexpression of PLT2 rescues the root meristem defects of the loss-of-function mutant of TPST. Together, these results support that TPST acts to maintain root stem cell niche by regulating basal- and auxin-induced expression of PLT1 and PLT2. TPST-dependent sulfation of RGFs provides a link between auxin and PLTs in regulating root stem cell niche maintenance.
State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
Wenkun
W
Zhou
Lirong
L
Wei
Jian
J
Xu
Qingzhe
Q
Zhai
Hongling
H
Jiang
Rong
R
Chen
Qian
Q
Chen
Jiaqiang
J
Sun
Jinfang
J
Chu
Lihuang
L
Zhu
Chun-Ming
CM
Liu
Chuanyou
C
Li
D017360:Arabidopsis / Q000033:anatomy & histology / Q000201:enzymology* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D018519:Meristem / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism; D009154:Mutation; D010802:Phylogeny; D018517:Plant Roots / Q000166:cytology* / Q000254:growth & development* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D055153:Stem Cell Niche; D015238:Sulfotransferases / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; C493246:PLT1 protein, Arabidopsis; C493247:PLT2 protein, Arabidopsis; D014157:Transcription Factors; D015238:Sulfotransferases; C039079:protein-tyrosine sulfotransferase