Two barley transformation systems, Agrobacterium-mediated and particle bombardment, were compared in terms of transformation efficiency, transgene copy number, expression, inheritance and physical structure of the transgenic loci using fluorescence in situ hybridisation (FISH). The efficiency of Agrobacterium-mediated transformation was double that obtained with particle bombardment. While 100% of the Agrobacterium-derived lines integrated between one and three copies of the transgene, 60% of the transgenic lines derived by particle bombardment integrated more than eight copies of the transgene. In most of the Agrobacterium-derived lines, the integrated T-DNA was stable and inherited as a simple Mendelian trait. Transgene silencing was frequently observed in the T1 populations of the bombardment-derived lines. The FISH technique was able to reveal additional details of the transgene integration site. For the efficient production of transgenic barley plants, with stable transgene expression and reduced silencing, the Agrobacterium-mediated method appears to offer significant advantages over particle bombardment.

The plastidial phosphoenolpyruvate (PEP)/phosphate translocator (PPT) is expressed in the developing embryos of oilseed rape (Brassica napus L.). PEP can be imported by plastids isolated from embryos and used for fatty acid synthesis at rates that are sufficient to account for one-third of the rate of fatty acid synthesis in vivo. This provides the first experimental evidence for uptake of PEP and incorporation of carbon from it into fatty acids by plastids. PEP metabolism in isolated plastids is able to provide some of the ATP required for fatty acid synthesis. Expression of the PPT and related glucose 6-phosphate (Glc-6-P) translocator (GPT) is high in early embryo and leaf development and then declines. The marked decline in the abundance of PPT and GPT transcripts between the pre- and mid-oil accumulating stages of embryo development in B. napus does not correlate with the corresponding translocator activities, which both increase over the same period. This means that transcript abundance cannot be used to infer the activity of the translocators.

A nearly complete skull and limited postcrania (SDSNH 146624), from the upper Oligocene of the Pysht Formation (Clallam County, Washington State, U.S.A.), represent a new species of Pinnarctidion, a pan-pinniped previously restricted to California and Oregon. Here, we describe SDSNH 146624 in detail and present results of a comprehensive phylogenetic analysis of early-diverging pan-pinnipeds. Pinnarctidion iverseni sp. nov., recognized on the basis of this specimen, is diagnosed by its posteriorly broad palate, anteriorly narrow rostrum, dorsoventrally deep zygomatic arches, and posterior accessory cusps on P3-4. Phylogenetic analysis recovered P. iverseni as most closely related to P. bishopi from the Jewett Sand of California's Central Valley. The well-preserved and reasonably complete skull and upper dentition of SDSNH 146624 help clarify relationships among the proximal outgroups of crown clade pinnipeds. http://zoobank.org/urn:lsid:zoobank.org:pub:94CCEFC9-472C-451A-A06B-7389B04919CE SUPPLEMENTAL DATA-Supplemental materials are available for this article for free at www.tandfonline.com/UJVP.

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