Gene Expression Studies Yield Clues on ‘Hybrid Vigor’
A group of scientists has used gene expression assays to explore the nature of hybrid vigor, or heterosis, the phenomenon that occurs in plants such as corn when different genetic lines are crossed, resulting in higher yields than either of the parental lines could produce themselves.
The researchers, Rentao Song and Joachim Messing of Rutgers University’s Waksman Institute of Microbio- logy, describe their findings in a paper, “Gene expression of a gene family in maize based on noncollinear haplotypes,” published in the July 22 issue of the Proceedings of the National Academy of Sciences, according to a statement issued by Rutgers this week.
Song and Messing took a region of a chromosome they had accurately mapped and compared it between two strains of maize, in hybrid crosses, and to corresponding regions in close relatives of maize — two kinds of rice. They also analyzed gene expression, comparing the maize strains and the hybrids.
They found that the same genome interval of the two maize varieties and their hybrids, all members of the same species, was substantially different in each, both in size and content. “Genes are missing or added, as are whole sequence segments that contain more than one gene,” wrote Song and Messing.
The results of the research showed that the combination of the radically different parental genomes in the offspring produced a hybrid genome where genes absent in one parent were supplied by the other. However, the expression data demonstrated a vigor exceeding what would be expected from the simple addition of prev- iously missing genes.
“The ‘whole’ — the hybrid offspring — turned out to be much greater than the sum of the parts,” said Messing, in a statement. “What we are finding is a synergism that is much more than just combining the two parents. Not only do the hybrids benefit from genes added by both parents, but their inheritance also includes additional regulatory factors. These two sources of heritable information may well constitute the binary system of the genetic world.”
Breandan Kennedy to Establish Zebrafish Facility at Conway Institute in Ireland
Breandan Kennedy, coming off a post-doctoral fellowship in the zebrafish research group at the University of Washington, will establish a zebrafish facility in Ireland, installing up to 400 tanks for the care of the tiny freshwater fish, which is used as a model organism for genomic studies, according to a statement issued last week by the Conway Institute of Biomolecular and Biomedical Research of the University College of Dublin.
Kennedy will begin research efforts when the new Conway Institute opens in August. The multidisciplinary institute is funded by Ireland’s Higher Education Authority; and by awards from the Health Research Board, Enterprise Ireland, BioResearch Ireland, the Wellcome Trust, the European Union, and bioindustry.
Kennedy’s research efforts, which will include microarray analysis, will focus on the study of the genes involved in the development and function of the eye in health and in blindness as well as the genetic make-up of the pineal gland, which controls circadian rhythms.
The Kennedy lab will seek to create fish models of disease, and use those to screen for drug treatment.
Expression Pathology Gets $100K SBIR To Develop Tissue Protein Array System
Rockville, Md.-based Expression Pathology announced last week a $100,000 Phase I Small Business Innovation Research grant from the National Institutes of Health to develop its tissue protein array technology.
The company uses a laser and microdissection techniques to array protein tissue and conduct high- throughput analysis of clinical material. It is developing a technology that enables the conversion of tissue embedded in paraffin into liquid to create its arrays.
Invitrogen Pays $2M for Rights to Genicon’s Signal Detection Technology
Invitrogen said it has paid Genicon Sciences $2 million for the rights to its nanoparticle signal generation and detection technology and products.
Genicon, of San Diego, which closed down in June, used gold and silver particles in its Resonance Light Scattering, or RLS, technology, and had used the technology for detection of proteins and nucleic acids, including in DNA and protein microarrays.
Genicon launched a DNA microarray toolkit in July 2002, and co-distributed the toolkit with Qiagen.
Carlsbad, Calif.-based Invitrogen said it plans to continue the co-distribution agreement with Qiagen for the DNA microarray toolkit in the short term, but will retain the exclusive worldwide commercialization rights for protein and other applications of RLS.