The AINTEGUMENTA LIKE1 homeotic transcription factor PtAIL1 controls the formation of adventitious root primordia in poplar.
Adventitious rooting is an essential but sometimes rate-limiting step in the clonal multiplication of elite tree germplasm, because the ability to form roots declines rapidly with age in mature adult plant tissues. In spite of the importance of adventitious rooting, the mechanism behind this developmental process remains poorly understood. We have described the transcriptional profiles that are associated with the developmental stages of adventitious root formation in the model tree poplar (Populus trichocarpa). Transcriptome analyses indicate a highly specific temporal induction of the AINTEGUMENTA LIKE1 (PtAIL1) transcription factor of the AP2 family during adventitious root formation. Transgenic poplar samples that overexpressed PtAIL1 were able to grow an increased number of adventitious roots, whereas RNA interference mediated the down-expression of PtAIL1 expression, which led to a delay in adventitious root formation. Microarray analysis showed that the expression of 15 genes, including the transcription factors AGAMOUS-Like6 and MYB36, was overexpressed in the stem tissues that generated root primordia in PtAIL1-overexpressing plants, whereas their expression was reduced in the RNA interference lines. These results demonstrate that PtAIL1 is a positive regulator of poplar rooting that acts early in the development of adventitious roots.
Institut National de la Recherche Agronomique and Lorraine University, Unité Mixte de Recherche Institut National de la Recherche Agronomique/Lorraine University 1136 Interactions Arbres/Micro-organismes, Institut National de la Recherche Agronomique-Nancy, 54280 Champenoux, France.
Adeline
A
Rigal
Yordan S
YS
Yordanov
Irene
I
Perrone
Anna
A
Karlberg
Emilie
E
Tisserant
Catherine
C
Bellini
Victor B
VB
Busov
Francis
F
Martin
Annegret
A
Kohler
Rishi
R
Bhalerao
Valérie
V
Legué
D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005801:Genes, Homeobox / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development*; D030821:Plants, Genetically Modified; D032107:Populus / Q000235:genetics* / Q000254:growth & development*; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome / Q000235:genetics
D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors