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Australian Breakthrough on 3-D Structure of Cancer Cell Protein.

Guidance Mechanism for Brain Stem Cells Discovered.

Synthetic Elastin for Tissue Repair in Humans.

Clue to Cause of Chronic Lung Disease Uncovered.

New Insights into Cause of Stomach Cancer.

Chinese Scientists Develop Salt-resistant Plants.

ED Study Yields Good Results.

CUHK Joins Drug Delivery Study for Posterior Uveitis.

Japanese Researchers Achieve Gene Targeting in Rice.

Device to Detect Tooth Decay in Advance.

Japan to Study Whether Cloned Cows are Safe to Eat.

Researchers Look for Clues to Slow Down Aging.

Malaysian Institute Applies Genetic Engineering to Crops and Fruits.

NZ Develops GM Potatoes.

Breakthrough Technique in Eye Surgery.

Researchers to Develop Biodegradable Heart Stent.

Taiwan Scientists Discover Gastric Cancer Markers.

Gene targeting to selected chromosomal loci is greatly stimulated when free DNA ends are created that initiate double-strand break repair. Gene therapy reagents can be developed by engineering DNA endonucleases that cleave genomes at desired target sequences. Homing endonucleases are naturally occurring rare-cutting enzymes that have well understood DNA binding and DNA cleavage properties. Rational design methods as well as directed evolution strategies that involve genetic selections and screens using combinatorial libraries generate homing endonucleases with altered sequence specificities. Molecular switches are being introduced into these enzymes to regulate their activity. This article reviews the progress that has been made in constructing homing endonucleases for gene therapy and genome engineering, and discusses the challenges that remain.

Embryonic stem (ES) cells are undifferentiated cell cultures that are derived from early developing animal embryos. ES cells retain the potential of differentiation into all cell types including germ cells and therefore provide a unique bridge linking in vitro and in vivo genetic manipulations. ES cells have been widely used in the production knockout mice. Attempts have been made to develop ES cells in fish. We used the medaka (Oryzias latipes) to develop the ES cell technology in a second vertebrate model. We have established feeder cell-free culture conditions and obtained several ES cell lines from midblastula embryos. These ES cells show all features of mouse ES cells including a diploid karyotype, the potential for differentiation into various cell types and chimera competence. This review is to use medaka ES cells to highlight the major advances and future prospects for obtaining and utilizing ES cells in model and aquaculture fish species.