Anther morphogenesis

Abstract: Ginseng (Panax ginseng), a valued medicinal herb, is a slow-growing plant that flowers after 3 years of growth with the formation of a solitary terminal umbel inflorescence. However, little is known about cytological events during ginseng reproduction, such as the development of the male organ, the stamen. To better understand the mechanism controlling ginseng male reproductive development, here, we investigated the inflorescence and flower structure of ginseng. Moreover, we performed cytological analysis of anther morphogenesis and showed the common and specialized cytological events including the formation of four concentric cell layers surrounding male reproductive cells followed by subsequent cell differentiation and degeneration of tapetal cells, as well as the formation of mature pollen grains via meiosis and mitosis during ginseng anther development. Particularly, our transverse section and microscopic observations showed that the ginseng tapetal layer exhibits obvious nonsynchronous cell division evidenced by the observation of one or two tapetal layers frequently observed in one anther lobe, suggesting the unique control of cell division. To facilitate the future study on ginseng male reproduction, we grouped the anther development into 10 developmental stages according to the characterized cytological events.

Abstract: The near absence of cell movement in plants makes clonal analysis a particularly informative method for reconstructing the early events of organ formation. We traced the patterns of cell division during maize anther development by inducing sector boundaries that preceded the earliest events of anther initiation. In doing this, we were able to estimate the smallest number of cells that are fated to form an anther, characteristic cell division patterns that occur during anther morphogenesis, and the relationship between the pre-existing symmetry of the initial cells and the final symmetry of the mature anther. Four general conclusions are made: (1) anthers are initiated from small groups of 12 or fewer cells in each of two floral meristematic layers; (2) the early growth of the anther is more like a shoot than a glume or leaf; (3) cell ancestry does not dictate basic structure and (4) the orientation of initial cells predicts the orientation of the four pollen-containing microsporangia, which define the axes of symmetry on the mature anther. The final point is discussed with other data, and an explanation involving a 'structural template' is invoked. The idea is that the orientation of initial cells within the floral meristem establishes an architectural pattern into which anther cells are recruited without regard to their cellular lineages. The structural template hypothesis may prove to be generally applicable to problems of pattern formation in plants.

Abstract: Major advances have been made in recent years in our understanding of anther development through a combination of genetic studies, cell biological technologies, biochemical analysis, microarray and high-throughput sequencing-based approaches. In this chapter, we summarize the widely used protocols for pollen viability staining; the investigation of anther morphogenesis by light microscopy of semi-thin sections; TUNEL assay for programmed tapetum cell death; and laser microdissection procedures to obtain specialized cells or cell layers for carrying out transcriptomics.

Abstract: Part I: Review and Overview Chapters 1. Flower Development in Arabidopsis - There is More to it than Learning your ABCs Nathanael Prunet and Thomas Jack 2. Flower Development in the Asterid Lineage Barry Causier and Brendan Davies 3. Grass Flower Development Hiro-Yuki Hirano, Wakana Tanaka, and Taiyo Toriba 4. Flower Diversity and Angiosperm Diversification Pamela S. Soltis and Douglas E. Soltis 5. Flower Development - Open Questions and Future Directions Frank Wellmer, John L. Bowman, Brendan Davies, Cristina Ferrandiz, Jennifer C. Fletcher, Robert G. Franks, Emmanuelle Graciet, Veronica Gregis, Toshiro Ito, Thomas P. Jack, Yuling Jiao, Martin M. Kater, Hong Ma, Elliot M. Meyerowitz, Nathanael Prunet, Jose Luis Riechmann PART II: Genetic and Phenotypic Analyses 6. Genetic Screens for Floral Mutants in Arabidopsis thaliana: Enhancers and Suppressors Thanh Theresa Dinh, Elizabeth Luscher, Shaofang Li, Xigang Liu, So Youn Won, and Xuemei Chen 7. Genetic and Phenotypic Analysis of Shoot Apical and Floral Meristem Development Mona M. Monfared and Jennifer C. Fletcher 8. Genetic and Phenotypic Analyses of Petal Development in Arabidopsis Judit Szecsi, Barbara Wippermann and Mohammed Bendahmane 9. Cell Biological Analyses of Anther Morphogenesis and Pollen Viability in Arabidopsisand Rice Fang Chang, Zaibao Zhang, Yue Jin, and Hong Ma 10. Molecular Cell Biology of Male Meiotic Chromosomes and Isolation of Male Meiocytes in Arabidopsis thaliana Yingxiang Wang, Zhihao Cheng, Pingli Lu, Ljudmilla Timofejeva, Hong Ma 11. Genetic and Phenotypic Analyses of Carpel Development in Arabidopsis Vicente Balanza, Patricia Ballester, Monica Colombo, Chloe Fourquin, Irene Martinez-Fernandez, and Cristina Ferrandiz Part III: Microscopy and Histology 12. Microscopic Analysis of Arabidopsis Ovules Balaji Enugutti and Kay Schneitz 13. Scanning Electron Microscopy Analysis of Floral Development Robert G. Franks 14. Detection of mRNA Expression Patterns by Non-radioactive in situ Hybridization on Histological Sections of Floral Tissue Anna Medzihradszky, Kay Schneitz, and Jan U. Lohmann 15. The GUS Reporter System in Flower Development Studies Janaki S. Mudunkothge and Beth A. Krizek Part IV: Experimental Systems 16. A Floral Induction System for the Study of Early Arabidopsis Flower Development Diarmuid O'Maoileidigh and Frank Wellmer 17. Fluorescence Activated Cell Sorting of Shoot Apical Meristem Cell Types G. Venugopala Reddy 18. Translating Ribosome Affinity Purification (TRAP) for Cell-specific Translation Profiling in Developing Flowers Ying Wang and Yuling Jiao 19. Laser-assisted Microdissection Applied to Floral Tissues Samuel E. Wuest and Ueli Grossniklaus PartV: Molecular Biology, Genomics, and Systems Biology 20. Identification of Arabidopsis Knock-out Lines for Genes of Interest Jose Tomas Matus, Thilia Ferrier, and Jose Luis Riechmann 21. Gene Expression Analysis by Quantitative Real-time PCR for Floral Tissues Mariana Bustamante, Jian Jin, Oriol Casagran, Tania Nolan, and Jose Luis Riechmann 22. Misexpression Approaches for the Manipulation of Flower Development Yifeng Xu, Eng-Seng Gan, and Toshiro Ito 23. Next Generation Sequencing Applied to Flower Development: RNA-Seq Jun He and Yuling Jiao 24. Next-Generation Sequencing Applied to Flower Development: ChIP-Seq Emmanuelle Graciet, Diarmuid Seosamh O'Maoileidigh, and Frank Wellmer 25. Live-Imaging of the Arabidopsis Inflorescence MeristemMarcus G. Heisler and Carolyn Ohno 26. Gene Regulatory Network Models for Floral Organ Determination Eugenio Azpeitia, Jose Davila-Velderrain, Carlos Villarreal, and Elena R. Alvarez-Buylla