Comparative transcriptomics among floral organs of the basal eudicot Eschscholzia californica as reference for floral evolutionary developmental studies.
BACKGROUND
Molecular genetic studies of floral development have concentrated on several core eudicots and grasses (monocots), which have canalized floral forms. Basal eudicots possess a wider range of floral morphologies than the core eudicots and grasses and can serve as an evolutionary link between core eudicots and monocots, and provide a reference for studies of other basal angiosperms. Recent advances in genomics have enabled researchers to profile gene activities during floral development, primarily in the eudicot Arabidopsis thaliana and the monocots rice and maize. However, our understanding of floral developmental processes among the basal eudicots remains limited.


RESULTS
Using a recently generated expressed sequence tag (EST) set, we have designed an oligonucleotide microarray for the basal eudicot Eschscholzia californica (California poppy). We performed microarray experiments with an interwoven-loop design in order to characterize the E. californica floral transcriptome and to identify differentially expressed genes in flower buds with pre-meiotic and meiotic cells, four floral organs at preanthesis stages (sepals, petals, stamens and carpels), developing fruits, and leaves.


CONCLUSIONS
Our results provide a foundation for comparative gene expression studies between eudicots and basal angiosperms. We identified whorl-specific gene expression patterns in E. californica and examined the floral expression of several gene families. Interestingly, most E. californica homologs of Arabidopsis genes important for flower development, except for genes encoding MADS-box transcription factors, show different expression patterns between the two species. Our comparative transcriptomics study highlights the unique evolutionary position of E. californica compared with basal angiosperms and core eudicots.
Zahn
Laura M
LM
Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA.
Ma
Xuan
X
Altman
Naomi S
NS
Zhang
Qing
Q
Wall
P Kerr
PK
Tian
Donglan
D
Gibas
Cynthia J
CJ
Gharaibeh
Raad
R
Leebens-Mack
James H
JH
Depamphilis
Claude W
CW
Ma
Hong
H
D017360:Arabidopsis / Q000235:genetics; D031675:Eschscholzia / Q000235:genetics* / Q000254:growth & development; D019143:Evolution, Molecular; D020224:Expressed Sequence Tags; D035264:Flowers / Q000235:genetics / Q000254:growth & development*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D008540:Meiosis; D020411:Oligonucleotide Array Sequence Analysis; D015345:Oligonucleotide Probes / Q000235:genetics; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D018749:RNA, Plant / Q000235:genetics
D015345:Oligonucleotide Probes; D018749:RNA, Plant