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Plant retinoblastoma homologues control nuclear proliferation in the female gametophyte

Abstract

Haploid spores of plants divide mitotically to form multicellular gametophytes. The female spore (megaspore) of most flowering plants develops by means of a well-defined programme into the mature megagametophyte consisting of the egg apparatus and a central cell1,2. We investigated the role of the Arabidopsis retinoblastoma3,4 protein homologue and its function as a negative regulator of cell proliferation during megagametophyte development. Here we show that three mutant alleles of the gene for the Arabidopsis retinoblastoma-related protein, RBR1 (ref. 4), are gametophytic lethal. In heterozygous plants 50% of the ovules are aborted when the mutant allele is maternally inherited. The mature unfertilized mutant megagametophyte fails to arrest mitosis and undergoes excessive nuclear proliferation in the embryo sac. Supernumerary nuclei are present at the micropylar end of the megagametophyte, which develops into the egg apparatus and central cell. The central cell nucleus, which gives rise to the endosperm after fertilization, initiates autonomous endosperm development reminiscent of fertilization-independent seed (fis) mutants5. Thus, RBR1 has a novel and previously unrecognized function in cell cycle control during gametogenesis and in the repression of autonomous endosperm development.

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References

  1. 1

    Grossniklaus, U. & Schneitz, K. The molecular and genetic basis of ovule and megagametophyte development. Semin. Cell Dev. Biol. 9, 227–238 (1998)

  2. 2

    Drews, G. N. & Yadegari, R. Development and function of the angiosperm female gametophyte. Annu. Rev. Genet. 36, 99–124 (2002)

  3. 3

    Durfee, T., Feiler, H. S. & Gruissem, W. Retinoblastoma-related proteins in plants: homologues or orthologues of their metazoan counterparts? Plant Mol. Biol. 43, 635–642 (2000)

  4. 4

    Kong, L. J. et al. A geminivirus replication protein interacts with the retinoblastoma protein through a novel domain to determine symptoms and tissue specificity of infection in plants. EMBO J. 19, 3485–3495 (2000)

  5. 5

    Grossniklaus, U., Spillane, C., Page, D. R. & Kohler, C. Genomic imprinting and seed development: endosperm formation with and without sex. Curr. Opin. Plant Biol. 4, 21–27 (2001)

  6. 6

    Howden, R. et al. Selection of T-DNA-tagged male and female gametophytic mutants by segregation distortion in Arabidopsis. Genetics 149, 621–631 (1998)

  7. 7

    Lin, B. Y. Structural modifications of the female gametophyte associated with indeterminate gametophyte (ig1) mutant in maize. Can. J. Genet. Cytol. 20, 249–257 (1978)

  8. 8

    Grossniklaus, U., Vielle-Calzada, J. P., Hoeppner, M. A. & Gagliano, W. B. Maternal control of embryogenesis by MEDEA, a polycomb group gene in Arabidopsis. Science 280, 446–450 (1998)

  9. 9

    Ohad, N. et al. A mutation that allows endosperm development without fertilization. Proc. Natl Acad. Sci. USA 93, 5319–5324 (1996)

  10. 10

    Kiyosue, T. et al. Control of fertilization-independent endosperm development by the MEDEA polycomb gene in Arabidopsis. Proc. Natl Acad. Sci. USA 96, 4186–4191 (1999)

  11. 11

    Luo, M. et al. Genes controlling fertilization-independent seed development in Arabidopsis thaliana. Proc. Natl Acad. Sci. USA 96, 296–301 (1999)

  12. 12

    Köhler, C. et al. Arabidopsis MSI1 is a component of the MEA/FIE Polycomb group complex and required for seed development. EMBO J. 22, 4804–4814 (2003)

  13. 13

    Lu, X. & Horvitz, H. R. lin-35 and lin-53, two genes that antagonize a C. elegans Ras pathway, encode proteins similar to Rb and its binding protein RbAp48. Cell 95, 981–991 (1998)

  14. 14

    Dahiya, A., Wong, S., Gonzalo, S., Gavin, M. & Dean, D. C. Linking the Rb and polycomb pathways. Mol. Cell 8, 557–569 (2001)

  15. 15

    Ach, R. A., Taranto, P. & Gruissem, W. A conserved family of WD-40 proteins binds to the retinoblastoma protein in both plants and animals. Plant Cell 9, 1595–1606 (1997)

  16. 16

    Weinberg, R. A. The retinoblastoma protein and cell cycle control. Cell 81, 323–330 (1995)

  17. 17

    Harbour, J. W. & Dean, D. C. The Rb/E2F pathway: expanding roles and emerging paradigms. Genes Dev. 14, 2393–2409 (2000)

  18. 18

    Ach, R. A. et al. RRB1 and RRB2 encode maize retinoblastoma-related proteins that interact with a plant D-type cyclin and geminivirus replication protein. Mol. Cell. Biol. 17, 5077–5086 (1997)

  19. 19

    De Veylder, L. et al. Control of proliferation, endoreduplication and differentiation by the Arabidopsis E2Fa-DPa transcription factor. EMBO J. 21, 1360–1368 (2002)

  20. 20

    Lee, E. Y. et al. Mice deficient for Rb are nonviable and show defects in neurogenesis and haematopoiesis. Nature 359, 288–294 (1992)

  21. 21

    Jacks, T. et al. Effects of an Rb mutation in the mouse. Nature 359, 295–300 (1992)

  22. 22

    Clarke, A. R. et al. Requirement for a functional Rb-1 gene in murine development. Nature 359, 328–330 (1992)

  23. 23

    Kwee, H. S. & Sundaresan, V. The NOMEGA gene required for female gametophyte development encodes the putative APC6/CDC16 component of the Anaphase Promoting Complex in Arabidopsis. Plant J. 36, 853–866 (2003)

  24. 24

    Du, W. & Dyson, N. The role of RBF in the introduction of G1 regulation during Drosophila embryogenesis. EMBO J. 18, 916–925 (1999)

  25. 25

    Honys, D. & Twell, D. Comparative analysis of the Arabidopsis pollen transcriptome. Plant Physiol. 132, 640–652 (2003)

  26. 26

    Yan, W., Kero, J., Suominen, J. & Toppari, J. Differential expression and regulation of the retinoblastoma family of proteins during testicular development and spermatogenesis: roles in the control of germ cell proliferation, differentiation and apoptosis. Oncogene 20, 1343–1356 (2001)

  27. 27

    Bracken, A. P. et al. EZH2 is downstream of the pRB-E2F pathway, essential for proliferation and amplified in cancer. EMBO J. 22, 5323–5335 (2003)

  28. 28

    Li, Y., Rosso, M. G., Strizhov, N., Viehoever, P. & Weisshaar, B. GABI-Kat SimpleSearch: a flanking sequence tag (FST) database for the identification of T-DNA insertion mutants in Arabidopsis thaliana. Bioinformatics 19, 1441–1442 (2003)

  29. 29

    Vielle-Calzada, J. P. et al. Maintenance of genomic imprinting at the Arabidopsis medea locus requires zygotic DDM1 activity. Genes Dev. 13, 2971–2982 (1999)

  30. 30

    Alexander, M. P. Differential staining of aborted and nonaborted pollen. Stain Technol. 44, 117–122 (1969)

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Acknowledgements

We are grateful to M. Collinge, J. Fütterer, U. Grossniklaus, M. Hanin and L. Hennig for discussions and critical reading of the manuscript. We thank J. Wyrzykowska and A. Johnston for help with in situ hybridization and ovule clearings. We also thank the Salk Institute Genomic Analysis Laboratory for providing the sequence-indexed Arabidopsis T-DNA insertion mutants and ABRC for providing us with seeds. This work was supported by funding from the Swiss National Science Foundation to W.G.

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Correspondence to Wilhelm Gruissem.

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The authors declare that they have no competing financial interests.

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Figure 1: Arabidopsis rbr1 mutant alleles induce ovule abortion and proliferation of nuclei in the egg apparatus.
Figure 2: The rbr1-1 mutant initiates a fertilization-independent endosperm and affects embryo and pollen development.
Figure 3: RBR1 is expressed in the female gametophyte and at different stages of flower development.

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