Research Highlights
KML’s founding director, Robert E. Kane, using the fertilized eggs of sea urchins as model cells, discovered the basic mechanism by which all cells divide their cytoplasm into two equal halves. The understanding of a major contractile protein lying just below the cell surface that literally pulled the cell into two parts was a seminal discovery. Kane went on to make major discoveries about the biochemistry of the mitotic spindle that separates the chromosomes, the structures that bear the genes, into equal parts during cell division adds to his prominence in the history of cell biology. Some of Kane’s last research focused on fertilization itself, with the notable discovery that it is the penetrating sperm, not the much larger egg itself, that determines the nature of the many changes that take place on the egg surface following fertilization. All of these discoveries now provide fundamental knowledge about our understanding of the biology of all cells, from amoebas to those in human organs.
Ian Gibbons switched his research focus from single-celled protozoans to the sperm of sea urchins when he joined the Kewalo Marine Laboratory. His focus was the mechanism that drives the beating or undulation of the cilia and flagella that serve thousands of different functions in all animals, from the movements of single-celled protozoans to clearing mucus and debris from our lungs. The sea urchin sperm, produced in the 10s of millions at each spawning, turned out to be a perfect ‘model cell’ for such studied, allowing literal dissection, by physical and biochemically, to determine which part of the fine structure of flagella carries out which part of the biophysical actions that result in regular, undulatory beating. The results of Gibbon’s research enabled a huge breadth of new research on, for example, how various pathogens impact ciliary activity (e.g., bacteria in the human lungs) or the results of loss of this activity (e.g., human cystic fibrosis). Gibbons was awarded the international Japan Prize for this research, all conducted at the Kewalo Marine Laboratory.
Tom Humphreys began research by studying a long-known phenomenon, the capacity of cells disaggregated from an entire sponge, to reaggregate to form a new body. He focused on cell adhesion, the capacity of cells to stick tightly to one another – important to all plants and animals – to make a major discovery about the ‘cement’ that holds cells together. After moving to the Kewalo Marine Lab, Humphreys research team focused on the developing sea urchin to join the very first investigations of the roles of genes in early animal development. And early discovery impacted understanding of the mechanisms by which genes direct development by messenger RNA. To carry out this work, Humphreys pioneered the isolation and sequencing of genes for the first time in Hawaii, from which they made some of the first discoveries about genetic segregation as a developmental mechanism. The greatest impact of this group came from their successes in studying the roles of RNA, the “messengers” in carrying out gene-directed developmental patterns.
Mike Hadfield’s lab has focused on animal metamorphosis, the rapid changes in cells, tissues and organs that transform a larva with one anatomy into a juvenile animal with a completely different anatomy, ecology and physiology. For most animals I the sea, these transformations occur when a larva leaves a swimming life in the plankton to join a community of its species on the bottom of the oceans. The lab group has found that, for most bottom-living invertebrate animals – those without backbones, making up more than 90% of animals living under salt water – the cues to settle and metamorphose arise from bacteria living in biofilms that coat all surfaces in the sea. Because the bacterial species making up biofilms differ between habitats, the research explains why larvae of different invertebrates settle in habitats suitable for them, whether it be a coral reef, rocky coast, sandy shore, inner estuary or the deep sea. This research also revealed the bacterial molecules that stimulate larval metamorphosis, acting as ectohormones to produce global responses in the animals’ bodies. It opened important avenues for discovering how bacterial molecules stimulate dramatic developmental changes.
Mark Martindale’s lab also focused on animal development, employing the embryos of different marine invertebrates as they proved to be useful for the study of various phenomena. The bulk of the work coming from the Martindale group pioneered understanding of embryonic patterning, that is how specific genes drive the formation of animal heads at one end of the embryo and tails at the other, or how right-left alignment occur, or dorsal (back) – ventral (belly) differentiation come about. Needless to say, results of Martindale’s research now appear in the textbooks to explain these basic developmental phenomena and are mined for their contributions to understanding what ‘went wrong’ when developmental anomalies (i.e., birth defects) occur.
The laboratories of Margaret McFall-Ngai and Ned Ruby focused on symbiotic interactions between animals and bacteria. They began working at Kewalo Marine Lab in 1996. Together, they developed the model symbiotic system between Euprymna scolopes, the Hawaiian bobtail squid, and Vibrio fischeri, a marine luminous bacterium. In 1996 their labs were the only ones studying this system. There are now over two dozen labs worldwide studying this symbiosis, principally with PIs whose education was in Margaret or Ned’s lab, or in labs of their academic ‘offspring’. While at KML, their research addressed questions concerning: (i) the host’s harvesting of symbionts each generation; (ii) genetic and biochemical basis of specificity of the association; (iii) development and maturation of the symbiotic relationship; (iv) factors driving persistence of the association; and, (v) the ecology and evolution of symbioses. Margaret and Ned left KML in 2004 to join the faculty of the University of Wisconsin-Madison. They returned to KML in 2014, continuing their collaboration on symbioses. Margaret served as the Director of the Pacific Biosciences Research Center until 2021.