Recommended
Recommended
More Related Content
Similar to Pre meiotic anther development Some basics
Similar to Pre meiotic anther development Some basics (20)
Recently uploaded
Recently uploaded (20)
Pre meiotic anther development Some basics
- 4. Produce and Disperse Pollen Androecium Stamens Stamens Represent Modified Leaves All Angiospermous Anthers are Bilobed and Quadrilocular (i.e., formed of four micro- sporangia) at an Early Stage of Development and This Condition is Seen in Most Mature Stamens. The final anther anatomy and the progression of developmental stagesaregenerallyconservedinangiosperms,althoughtherearemanyv ariationsinanthergrowth parameters , number of days to anthesis, and mechanisms of pollen shed (the termination ofanther development)
- 5. Why to Study Anther Development ?
- 9. Mamun, E. Al, Cantrill, L. C., Overall, R. L., & Sutton, B. G., https://doi.org/10.1016/j.cellbi.2005.05.009 (2005).
- 10. Upper Row A-Epidermis C&D-Endothecium Lower Row D-Middle Layer A-Tapetum C-Sprogenous Cell
- 12. Walbot, V., & Egger, R. L. (2016). Pre-Meiotic Anther Development: Cell Fate Specification and Differentiation. Annual Review of Plant Biology, (December 2015), 1–31. https://doi.org/10.1146/annurev-arplant-043015-111804 Mamun, E. Al, Cantrill, L. C., Overall, R. L., & Sutton, B. G. (2005). Cellular organisation and differentiation of organelles in pre-meiotic rice anthers. Cell Biology International, 29(9), 792–802. https://doi.org/10.1016/j.cellbi.2005.05.009 Scott, R. J. (2004). Stamen Structure and Function. The Plant Cell Online, 16(suppl_1), S46–S60. https://doi.org/10.1105/tpc.017012 Goldberg, R. B., Beals, T. P., & Sanders, P. M. (1993). Anther Development : Basic Principles and Pract ical Applicat ions. The Plant Cell, 5(10), 1217–1229. Wang, C.-J. R., Nan, G.-L., Kelliher, T., Timofejeva, L., Vernoud, V., Golubovskaya, I. N., … Cande, W. Z. (2012). Maize multiple archesporial cells 1 (mac1), an ortholog of rice TDL1A, modulates cell proliferation and identity in early anther development. Development, 139(14), 2594–2603. https://doi.org/10.1242/dev.077891 Toriba, T., Suzaki, T., Yamaguchi, T., Ohmori, Y., Tsukaya, H., & Hirano, H.-Y. (2010). Distinct regulation of adaxial-abaxial polarity in anther patterning in rice. The Plant Cell, 22(5), 1452–1462. https://doi.org/10.1105/tpc.110.075291
- 13. Thank You Have A Nice Day
Editor's Notes
- Fig. 2. (A) Typical epidermal cells with thick external walls covered in cuticle, most cells also having a large central vacuole with the tonoplast membrane visible (arrowheads). Plasmodesmata connect the adjacent cells (arrows). Nucleoli were observed within the nuclei. (B) At high magnification the bi-lamellate nature of the evenly distributed cuticle on the epidermal cells (arrows) is apparent. (C,D) Portions of endothecium cells exhibiting numerous starch containing chloroplasts and clusters of small mitochondria respectively. In (D), a region of cortical cytoplasm, lipid bodies and microtubules are also visible (arrows). en, endothecium; chl, chloroplast; m, mitochondrion; p, plastid; v, vacuole; s, starch granule; lb, lipid body; mt, microtubules; neo, nucleolus. Fig. 4. (A) The chloroplasts in the endothecium contain starch granules surrounded by immature but well defined thylakoids and grana. Microbodies were often associated with the chloroplasts. (B) Amyloplasts are also present in the endothecium. (C) A section of cell wall between neighbouring endothecium cells showing a plasmodesma (arrows) linking the cells. (D) Middle layer cell during pre-meiotic development exhibiting a central nucleus with mitochondria, plastids and vacuoles. (E) Middle layer cells are connected with one another by plasmodesmata. en, endothecium; ml, middle layer; n, nucleus; v, vacuole; lb, lipid body; m, mitochondrion; am, amyloplast; p, plastid; th, thylakoid; gr, grana; mb, microbody. Fig. 5. (A) Tapetal cells exhibiting large central nuclei, numerous mitochondria, small vacuoles, vesicles, lipid bodies and plastids. The nuclear envelope displays dilatation with large spaces present between the double membranes (arrowheads). In the neighbouring sporogenous cell, electron opaque bodies are visible near the cells wall (arrows). (B) Like the surrounding tapetal cells, the sporogenous cells are densely cytoplasmic with numerous organelles. (C) High magnification image of sporogenous cells containing numerous organelles, many of which are similar in size and shape and in a relatively undifferentiated state. Lipid bodies and numerous vesicles of different sizes including electron opaque bodies are also seen in the cytoplasm close to the cell wall (arrows). (D,E) Plasmodesmata (arrows) exist between tapetal cells, and tapetal and middle layer cells (D) and neighbouring sporogenous cells. (F) Detail of cell wall between tapetum and sporogenous cells indicating wall thickenings (arrows). t, tapetum; ml, middle layer; m, mitochondrion; p, plastid; lb, lipid body; r, ribosomes; v, vacuole; n, nucleus; neo, nucleolus; ch, chromatin; sp, sporogenous cell; vs, vesicle.
- Fig. 8. Phenotypic characterization of the mac1; ocl4 double mutant. (A-D)Transverse section of anther lobes. (A)In the wild-type anther (500m), four cell types are present: the epidermis (EP), endothecium (EN), secondary parietal cells (SPC) and archesporial cells (AR). The EN cells are elongated and have started to accumulate starch granules. (B)In the ocl4 mutant, after L2-d cells have divided periclinally to form two layers, the outer layer divided periclinally again to form two EN-like cell layers. (C)In the mac1 mutant, excess AR cells are observed. An EN-like layer with starch granules forms from a few cell layers with unknown identity. (D)In the mac1; ocl4 double mutant, excess AR cells are present with unorganized somatic cells surrounding them. In addition, two EN-like layers form (blue dotted lines). The border of AR cells is evident in both wildtype (A) and the ocl4 mutant (B) (green dotted lines); however, it becomes disordered in the mac1 mutant (C) and mac1; ocl4 double mutant (D). (E-H)Confocal images of longitudinal optical sections of anthers. (E)A wild-type locule (500m anther) illustrates that EN and SPC have differentiated. (F)A 450m mac1 anther shows that excess AR cells enclosed by one layer of cells derived from L2 (L2-d) and EP. (G)A mac1; ocl4 double mutant anther (500m) shows an increased number of AR plus irregular patches of two somatic cell layers (arrowhead). (H)A mac1; ocl4 double mutant anther (1 mm) exhibits a burst of cell divisions as seen in mac1 mutant. Scale bars: 20m.