Abolition of the tapetum suicide program ruins microsporogenesis

Plant Cell Physiol. 2006 Jun;47(6):784-7. doi: 10.1093/pcp/pcj039. Epub 2006 Mar 25.


Microsporogenesis in angiosperms takes places within the anther. Microspores are surrounded by a layer of cells, the tapetum, which degenerates during the later stages of pollen development with cytological features characteristic of programmed cell death (PCD). We report herein that the expression of AtBI-1, which suppresses Bax-induced cell death, in the tapetum at the tetrad stage inhibits tapetum degeneration and subsequently results in pollen abortion, while activation of AtBI-1 at the later stage does not. Our results demonstrate that the PCD signal commences at the tetrad stage and that the proper timing of PCD in the tapetum is essential for normal microsporogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / physiology
  • Arabidopsis / cytology*
  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / physiology*
  • Cell Death / drug effects
  • Cell Death / physiology
  • Gene Expression Regulation, Plant / drug effects
  • Gene Expression Regulation, Plant / physiology
  • Genes, Plant / genetics
  • In Situ Nick-End Labeling
  • Membrane Proteins / genetics
  • Membrane Proteins / physiology
  • Mice
  • Pollen / cytology*
  • Pollen / growth & development*
  • Pollen / physiology
  • Time Factors
  • bcl-2-Associated X Protein / pharmacology


  • ATBI-1 protein, Arabidopsis
  • Apoptosis Regulatory Proteins
  • Arabidopsis Proteins
  • Membrane Proteins
  • Tapetum determinant1 protein, Arabidopsis
  • bcl-2-Associated X Protein