The findings, detailed June 5 in the online early edition of the journal Proceedings of the National Academy of Sciences, present evidence that individual centrosomes within a cell may carry their own genetic material.
"Our research provides direct biochemical evidence that RNA is present in the centrosomes of clam cells," says Robert Palazzo, professor of biology and director of the Center for Biotechnology and Interdisciplinary Studies at Rensselaer.
Palazzo's laboratory isolated clam centrosomes and Mark Alliegro and Mary Anne Alliegro of LSU Health Sciences Center analyzed the centrosomes for RNA content.
"Although the possibility of DNA inside the centrosome of the cell has been ruled out by others' previous work, the presence of RNA had not been confirmed or denied until now," says Palazzo. "Our results show there are at least five specific forms of RNA in the clam cell centrosome which could be related to structure, encoding of proteins, or the regulation of organism development. The specific role or function of the RNA in the centrosome and its possible involvement in the development of animals will be significant questions in continuing studies.
"Since RNA guides the translation of genes into proteins, knowing more about its role(s) in the centrosome may help researchers better understand the progression of diseases such as cancer, which has been linked to abnormal centrosome numbers in tumor cells," says Palazzo.
The study on surf clam centrosomes was initiated at the MBL, an international biological research center where scientists use locally abundant marine organisms like surf clams and their eggs as research models. Clam eggs are modeled as simple versions of human cells, and biologists who study cell division value them for several reasons, according to Palazzo. The eggs develop fast, entering the process of cell division less than 15 minutes after fertilization, and, once fertilized, divide in synch every 30-50 minutes -- providing billions of biochemically identical cells to study.
Using a purification technique Palazzo developed at the MBL, the scientists were able to isolate relatively large quantities of clam centrosomes for their research. Palazzo collaborated with Mark Alliegro and Mary Anne Alliegro during summers at the MBL.
In addition to his position as director of the Center for Biotechnology and Interdisciplinary Studies at Rensselaer, Palazzo also holds appointments at the MBL as visiting summer researcher and at the Wadsworth Center of the New York State Department of Health as research scientist.
The research was funded by the National Institute of General Medical Sciences of the National Institutes of Health.
Biotechnology and Interdisciplinary Studies at Rensselaer
At Rensselaer, faculty and students in diverse academic and research disciplines are collaborating at the intersection of the life sciences and engineering to encourage discovery and innovation. Rensselaer's four biotechnology research constellations -- biocatalysis and metabolic engineering, functional tissue engineering and regenerative medicine, biocomputation and bioinformatics, and integrative systems biology -- engage a multidisciplinary mix of faculty and students focused on the application of engineering and physical and information sciences to the life sciences. Ranked among the world's most advanced research facilities, the Center for Biotechnology and Interdisciplinary Studies at Rensselaer provides a state-of-the-art platform for collaborative research and world-class programs and symposia.
About Rensselaer
Rensselaer Polytechnic Institute, founded in 1824, is the nation's oldest technological university. The university offers bachelor's, master's and doctoral degrees in engineering, the sciences, information technology, architecture, management, and the humanities and social sciences. Institute programs serve undergraduates, graduate students and working professionals around the world. Rensselaer faculty are known for preeminence in research conducted in a wide range of fields, with particular emphasis in biotechnology, nanotechnology, information technology, and the media arts and technology. The Institute is well known for its success in the transfer of technology from the laboratory to the marketplace so that new discoveries and inventions benefit human life, protect the environment, and strengthen economic development.
Journal
Proceedings of the National Academy of Sciences