Inflorescence commitment and architecture in Arabidopsis

Science

Volumn 275, Issue 5296, 1997, Pages 80-83

  Bradley, Desmond ^a   Ratcliffe, Oliver ^b   Vincent, Coral ^b   Carpenter, Rosemary ^b   Coen, Enrico ^b  

^a SAINSBURY LABORATORY   (United Kingdom)

^b JOHN INNES CENTRE   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

ARABIDOPSIS; ARTICLE; CONTROLLED STUDY; GENE EXPRESSION; GENE MUTATION; NONHUMAN; PLANT GROWTH; PRIORITY JOURNAL; SEQUENCE HOMOLOGY;

AMINO ACID SEQUENCE; ARABIDOPSIS; ARABIDOPSIS PROTEINS; EVOLUTION; EXONS; GENE EXPRESSION; GENES, PLANT; MERISTEM; MOLECULAR SEQUENCE DATA; MUTATION; PLANT PROTEINS; PLANTS;

EID: 0031015315     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.275.5296.80     Document Type: Article

References (32)

1. F. Weberling, Morphology of Flowers and Inflorescences (Cambridge Univ. Press, Cambridge, 1989).
2. E. S. Coen, Annu. Rev. Plant Physiol. Plant Mol. Biol. 42, 241 (1991).
3. _ and J. M. Nugent, Development (suppl.) (1994), p. 107.
4. H. W. Rickett, Bot. Rev. 10, 187 (1944).
5. G. L. Stebbins, Flowering Plants, Evolution Above the Species Level (Harvard Univ. Press, Cambridge, MA, 1974).
6. H. Kuckuck and R. Schick, Z. lndukt. Abstammungs-Vererbungsl. 56, 51 (1930); H. Stubbe, Genetik und Zytologie von Antirrhinum L. sect. Antirrhinum (VEB Gustav Frischer, Jena, 1966).
7. H. Kuckuck and R. Schick, Z. lndukt. Abstammungs-Vererbungsl. 56, 51 (1930); H. Stubbe, Genetik und Zytologie von Antirrhinum L. sect. Antirrhinum (VEB Gustav Frischer, Jena, 1966).
8. D. Bradley et al., Nature 379, 791 (1996).
9. S. Shannon and D. R. Meeks-Wagner, Plant Cell 3, 877 (1991).
10. J. Alvarez, C. L. Guli, X.-H. Yu, D. R. Smyth, Plant J. 2, 103 (1992).
11. All tfl1 alleles in the Columbia background show significant reduction in the time to flowering, under both LD (16 or more hours of light per day) and SD (10 or fewer hours of light per day) at ∼ 20° to 25°C (8, 11). A weaker effect was reported for tfl1 alleles in the Landsberg erecta background (9). The flowering time phenotype is semidominant (8, 11).
12. E. A. Schultz and G. W. Haughn, Development 119, 745 (1993).
13. In plants carrying strong tfl1 alleles, one to five lateral flowers are generated below the terminal flower when plants are grown under LD, whereas more than 20 flowers are generated under SD (8, 9). Increasing the growth temperature results in fewer flowers being generated before the terminal flower (9). Plants carrying weak tfl1 alleles can produce more than 60 flowers before the terminal flower, although this number is markedly reduced when plants grow at a higher temperature (9).
14. The terminal flowers of tfl1 mutant plants often vary in their organ numbers and arrangement relative to wild-type flowers (8, 9, 11). Wild-type flowers are composed of four whorls of organs: four sepals outermost, four petals, six stamens, and two central, fused carpels. In tfl-1 mutants, the terminal flower and one or two flowers generated below may be partially united at the apex. Organ primordia may arise in a mix of whorls and spirals, with some organs apparently fused together. Mosaic organs may occur, with patches of one floral organ type mixed with another. The number of each organ type is often less than in the wild type, though carpels are usually normal.
15. An Arabidopsis genomic clone was obtained by screening a Landsberg erecta library [G.C. Whitelam et al., Plant Cell 5, 757 (1993)] with the CEN cDNA (7). About 80,000 recombinants were screened at 60°C and washed at 60°C with 0.4x SSC and 0.5% SDS, as described (22). Of five positives, one yielded EL, a 14-kb Xba I fragment that was subcloned into Bluescript KS+ vector (Stratagene) to give pJAM2043. A 2-kb Eco Rl-Xba I fragment of pJAM2043 contained all of the CEN-hybridizing signal and was subcloned as pJAM2044.
16. Database searches involved BLAST [S. F. Altschul, W. Gish, W. Miller, E. W. Myers, D. J. Lipman, J. Mol. Biol. 215, 403 (1990)] and FASTA [W. R. Pearson and D. J. Lipman, Proc. Natl. Acad. Sci. U.S.A. 85, 2444 (1988)]. The Arabidopsis clone 129D7T7 was obtained from the Arabidopsis Biological Resource Center at Ohio State University (Columbus, OH) and was originally isolated from Arabidopsis thaliana ecotype Columbia; see T. Newman et al. at Michigan State University (East Lansing, Ml) (accession number T44654).
17. Database searches involved BLAST [S. F. Altschul, W. Gish, W. Miller, E. W. Myers, D. J. Lipman, J. Mol. Biol. 215, 403 (1990)] and FASTA [W. R. Pearson and D. J. Lipman, Proc. Natl. Acad. Sci. U.S.A. 85, 2444 (1988)]. The Arabidopsis clone 129D7T7 was obtained from the Arabidopsis Biological Resource Center at Ohio State University (Columbus, OH) and was originally isolated from Arabidopsis thaliana ecotype Columbia; see T. Newman et al. at Michigan State University (East Lansing, Ml) (accession number T44654).
18. The Arabidopsis EST was mapped to the top of chromosome 5, above the restriction fragment length polymorphism marker 447 (R. Schmidt, personal communication), in agreement with previous mapping (8, 9).
19. Wild-type Arabidopsis (Columbia) and plants carrying alleles tfl1-1, tfl1-11, tfl1-13, or tfl-14 were grown on soil under LD. Seeds carrying tfl1 alleles were obtained from the Arabidopsis Biological Resource Center at Ohio State University. Genomic DNA was isolated from wild-type and mutant plants by means of a miniprep method (R. Simon, personal communication). Leaf tissue was homogenized while frozen, buffer [50 mM EDTA, 0.1 M tris-HCl (pH 8), and 1% SDS] was added, and the sample was thawed at 65°C for 2 min. DNA was extracted with phenol, phenol/chloroform (1:1), and chloroform, and precipitated with isopropanol and sodium acetate. After an ethanol wash, DNA was resuspended in tris-EDTA containing ribonuclease. Oligonucleotide primers were designed to sequences ∼160 bp upstream of the ATG and 120 bp downstream of the stop codon. To avoid polymerase chain reaction (PCR) artifacts, we carried out three separate PCRs on each DNA preparation and cloned one PCR product from each into pGEM-T vector (Promega). Each clone of ∼1.3 kb was sequenced using the ABI Prism system (Perkin-Elmer), and only base changes present in all three PCR products for any one allele were considered genuine.
20. The rice clone S19461A was obtained from the National Institute of Agrobiological Resource Rice Genome Resource Project (RGP), lbaraki, Japan, and was isolated from Oryza sativa (GenBank accession number D40166). The partial sequence of the rice clone R29181A (GenBank accession number D24998) was made by M. Yuzo and S. Takuji (RGP, lbaraki, Japan) and was obtained from the databases (15).
21. D. K. Grandy et. al., Mol. Endocrinol. 4, 1370 (1990); S. Bucquoy, P. Jolles, F. Schoentgen, Eur. J. Biochem. 225, 1203 (1994).
22. D. K. Grandy et. al., Mol. Endocrinol. 4, 1370 (1990); S. Bucquoy, P. Jolles, F. Schoentgen, Eur. J. Biochem. 225, 1203 (1994).
23. D. Weigel, J. Alvarez, D. R. Smyth, M. F. Yanofsky, E. M. Meyerowitz, Cell 69, 843 (1992); D. Weigel and O. Nilsson, Nature 377, 495 (1995).
24. D. Weigel, J. Alvarez, D. R. Smyth, M. F. Yanofsky, E. M. Meyerowitz, Cell 69, 843 (1992); D. Weigel and O. Nilsson, Nature 377, 495 (1995).
25. D. Bradley, O. Ratcliffe, C. Vincent, R. Carpenter, E. Coen, data not shown.
26. D. Bradley, R. Carpenter, H. Sommer, N. Hartley, E. Coen, Cell 72, 85 (1993).
27. Sequence alignment programs used the GCG package (University of Wisconsin).
28. Wild-type plants of Arabidopsis thaliana ecotype Columbia were grown under 16 hours light/8 hours dark and harvested just as plants showed signs of bolting. Methods for digoxigenin labeling of RNA probes, tissue preparation, and in situ hybridization were as described (see (22)]. Double labeling first involved digoxigenin-labeled antisense TFL1 RNA and purple color detection, followed by fluorescein isothiocyanate-labeled antisense LFY RNA and red color [P. R. Fobert, E. S. Coen, G. J. P. Murphy, J. H. Doonan, EMBO J. 13, 616 (1994)]. The TFL1 probe was made with the plasmid pJAM2045. This plasmid contained an internal fragment of ∼500 bp of TFL 1, generated by PCR and subcloned into pGEM-T vector (Promega). The LFY probe was made from the plasmid pDW122 as described (20).
29. Wild-type and tfl1-1 mutant plants were imbibed at 4°C for 5 days in the dark, before sowing on soil under LD (16 hours light/8 hours dark) or SD (8 hours light/16 hours dark). Plants were transferred at daily intervals from LD to SD and scored when plants had bolted. Assigning leaves to the basal, primary rosette was difficult for plants exhibiting the SD phenotype as secondary shoots developed. This variation was reflected in greater standard errors. SEM analysis confirmed the scoring of plants exhibiting a LD phenotype.
30. M. H. Williams and P. B. Green, Protoplasma 147, 77 (1988); D. R. Smyth, J. L. Bowman, E. M. Meyerowitz, Plant Cell 2, 755 (1990).
31. M. H. Williams and P. B. Green, Protoplasma 147, 77 (1988); D. R. Smyth, J. L. Bowman, E. M. Meyerowitz, Plant Cell 2, 755 (1990).
32. We thank P. Bovill and D. Barker for help in sequencing the tfl1 alleles; D. Weigel for plasmid pDW122; G. Ingram and R. Simon for advice on manipulation of Arabidopsis; R. Schmidt and C. Dean for mapping of the Arabidopsis EST; the Arabidopsis Biological Resource Center at Ohio State University (Columbus, OH) and T. Sasaki et al. of the Rice Genome Resource Project (lbaraki, Japan) for clones; E. Schultz for helpful discussions on TFL1; and I. Amaya, P. Cubas, and S. Doyle for comments. Supported by grants to E.C. and R.C. from the UK Biotechnology and Biological Sciences Research Council (BBSRC) PMB2 and Stem Cell Programmes, the European Economic Community AMICA program, and Gatsby Foundation. D.B. was also supported by a BBSRC Fellowship and the Sainsbury Laboratory.