Just published this month. But this is a small case of self promotion, since I got a somewhat low rank in authorship… But hey, that’s still counting, isn’t it?* :-p
I think I could comment on specific points made in the manuscript where my personnal interpretation of the data begins to depart from those made in the paper, but since I never really blogged about microsporogenesis, I’ll let it to the most interested readers (those who will read it because the article is mentionned here, if there’s any ;-)
PHYLOGENETIC COMPARATIVE ANALYSIS OF MICROSPOROGENESIS IN ANGIOSPERMS WITH A FOCUS ON MONOCOTS
S. Nadot, C. A. Furness, J. Sannier, L. Penet, S. Triki-Teurtroy, B. Albert, and A. Ressayre
American Journal of Botany 95(11): 1426–1436. 2008.
Abstract: This paper presents the fi rst broad overview of three main features of microsporogenesis (male meiosis) in angiosperms: cytokinesis (cell division), intersporal wall formation, and tetrad form. A phylogenetic comparative approach was used to test for correlated evolution among these characters and to make hypotheses about evolutionary trends in microsporogenesis. The link between features of microsporogenesis and pollen aperture type was examined. We show that the pathway associated with successive cytokinesis (cytoplasm is partitioned after each meiotic division) is restricted to wall formation mediated by centrifugally developing cell plates, and tetragonal (or decussate, T-shaped, linear) tetrads. Conversely, much more fl exibility is observed when cytokinesis is simultaneous (two meiotic divisions completed before cytoplasmic partitioning). We suggest that the ancestral type of microsporogenesis for angiosperms, and perhaps for all seed plants, associated simultaneous cytokinesis with centripetal wall formation, resulting in a large diversity in tetrad forms, ranging from regular tetrahedral to tetragonal tetrads, including rhomboidal tetrads. From this ancestral pathway, switches toward successive cytokinesis occurred among basal angiosperms and monocots, generally associated with a switch toward centrifugal intersporal wall formation, whereas eudicots evolved toward an almost exclusive production of regular tetrahedral tetrads. No straightforward link is found between the type of microsporogenesis and pollen aperture type.
Key words: comparative analysis; correlated evolution; cytokinesis; intersporal wall formation; microsporogenesis; pollen aperture type; tetrad form.
* Contrary to common wisdom among scientistststs, many authors may reasonnably contribute to a manuscript, to a point that warrants authorship -in this very case, there are actually two gross categories of authors with regard to contributions.