75 Integrating Membrane Transport with Male Gametophyte ... - TAIR

361 Evaluation of Arabidopsis FOX line: T2 phenotype and phenotype recapitulation by
transformation
Takanari Ichikawa 1 , Miki Nakazawa 1 , Youichi Kondou 1 , Akie Ishikawa 1 , Mika Kawashima 1 , Haruko Iizumi 1 , Motoaki
Seki 1 , Miki Fujita 2 , Syu Muto 3 , Kazuo Shinozaki 1 , Minami Matsui 1
1
RIKEN PSC, 2 CREST, JST,, 3 NEC,soft,Ltd.
We describe here the establishment of a novel gain of function system named as Fox hunting system (Full-length cDNA
over-expresser gene-hunting system) for random over-expression of a normalized Arabidopsis full-length cDNA library.
Full-length cDNAs from Arabidopsis were sequenced and c.a. 10,000 non-redundant clones were randomly expressed
in Arabidopsis plants. We observed 1,487 morphological mutant candidates while growing 15,547 T1 transformants.
One of the most frequently observed phenotypes was that of pale green leaves and stems. When 115 such T2 lines were
observed 59 of these lines showed the pale green phenotype in dominant or semi-dominant fashion. We will introduce
10 different lines that showed the visible phenotypes upon retransformation of the wild type plant with the rescued fulllength
cDNAs. Applications of this system on rice functional genomics will be discussed.
362 Population Genetic Variation in Flowering Time Response among Seasonal and Geographic
Light Conditions
Yan Li, Peter Roycewicz, Justin Borevitz
Department of Ecology and Evolution, University of Chicago
Large genetic variation for the flowering time has been observed in different Arabidopsis thaliana accessions that
is influenced by day length. We have collected 1000s of new lines from various Midwestern sites across different times
of year. These lines and others are being genotyped for > 100 common SNPs to survey population and seasonal genetic
variation. Unique lines will be available and are being phenotyped for flowering time in simulated seasonal conditions
representing Spain and Sweeden. Our growth chambers contain far-red, red, true-white, and blue fluorescent bulbs on
electronically dimmable ballasts the recreate daily sunrise, bright midday, and sunset conditions. The intensity, light
quality spectrum, and day length, changes throughout the year and is more dramatic in Spain vs Sweeden. Temperature and
humidity also cycle throughout the day and year accordingly. We have already used these conditions to map Quantitative
trait loci (QTL) responsible for spring flowering time in the accessions of Kas/Col RIL set across 2 replicate blocks. A
linkage map from 96 RILs (~12 plants each) was established using 119 markers (64 new SNPs and 55previous ones). One
major QTL mapping to the FRIGIDA (FRI) locus, was detected on the top of chromosome 4 that had differential effects
depending on the geographic condition. Other minor QTL were unique to particular geographic locations. These GxE
QTL suggest that subtle changes in light quality, rate of change of day length, and temperature are differentially felt by
known and novel alleles controlling flowering time and may be responsible for adaptation to regional environments.