RT Journal Article
SR Electronic
T1 Auxin signaling is a common factor underlying natural variation in tomato shade avoidance
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 031088
DO 10.1101/031088
A1 Susan M. Bush
A1 Leonela G. Carriedo
A1 Daniel Fulop
A1 Yasunori Ichihashi
A1 Mike F. Covington
A1 Ravi Kumar
A1 Aashish Ranjan
A1 Daniel Chitwood
A1 Lauren Headland
A1 Daniele L. Filiault
A1 José M. Jiménez-Goméz
A1 Neelima R. Sinha
A1 Julin N. Maloof
YR 2015
UL http://biorxiv.org/content/early/2015/11/23/031088.abstract
AB Light is an essential resource for photosynthesis. Limitation of light by shade from plant neighbors can induce a light competition program known as the shade avoidance response (SAR), thereby altering plant growth and development for the sake of survival. Natural genetic variation in SAR is found in plants adapted to distinct environments, including domesticated tomato Solanum lycopersicum and its wild relative Solanum pennellii. QTL mapping was used to examine variation of the SAR between these two species. We found organ specific responses in the elongation of the stem and petiole, including developmental acceleration of growth. Through RNAseq analysis we identified a number of ILs with reduced expression of auxin-related genes in shade treatment. These same ILs display a shade tolerant phenotype in stem growth and overall height. We also identified ILs with altered SAR expression of cell wall expansion genes, although these genotypes had no accompanying alteration in phenotype. Examination of weighted gene co-expression Connectivity networks in sun- and shade-treated plants revealed Connectivity changes in auxin and light signaling genes; this result was supported by the Identification of motifs within the promoters of a subset of shade-responsive genes that were enriched in light signaling, developmental pathways, and auxin responsive transcriptional domains. The Identification ofboth systemic and organ-specific shade tolerance in the ILs, as well as associated changes in the transcriptome, has the potential to inform future studies for breeding plants able to be grown closely (while neighbor-shaded), yet still maintaining high yield.Summary Growth plasticity in response to shade involves expression of specific auxin signaling and cell wall expansion genes, and shade avoidance QTL affect both stem elongation and developmental rate.