Drs. Joseph Scott and Sharon Broadwater of the College of William and Mary are studying the details of cell division in groups of red algae (Rhodophyta) using scanning and transmisson electron microscopy. The number, kinds, and orientations of subcellular structures combine to create patterns of cell division that appear to be characteristic for major groups of red algae at the ordinal or subclass taxonomic level. Research is continuing on cell division patterns in groups of Corallinales and Batrachospermales, which at present are poorly known. The investigators are also conducting a search in red algae for the recently described protein centrin, which is a contractile protein thought to be present in all eukaryotic cells and involved in chromosome movement. In addition, the enigmatic unicellular organism Glaucosphaera vacuolata is being studied through electron microscopy and molecular and immunocytochemical methods. One of the unique characters of Rhodophyta, alone among the world's algae, is the lack of a flagellar apparatus, yet Drs. Scott and Broadwater have preliminary data indicating that G. vacuolata possesses a non-emergent flagellum located within a red-algal cytoplasm. Molecular and immunocytochemical tests are being made with the help of collaborators, to confirm the presence of centrin and of a reduced flagellum. The results will provide new insights into phylogenetic relationships within the red algae and with other groups of primitive organisms.
