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• The hyperaccumulator Pteris vittata translocates arsenic (As) from roots to fronds efficiently, but the form of As translocated in xylem and the main location of arsenate reduction have not been resolved. • Here, P. vittata was exposed to 5 µM arsenate or arsenite for 1–24 h, with or without 100 µM phosphate. Arsenic speciation was determined in xylem sap, roots, fronds and nutrient solutions by high-performance liquid chromatography (HPLC) linked to inductively coupled plasma mass spectrometry (ICP-MS). • The xylem sap As concentration was 18–73 times that in the nutrient solution. In both arsenate- and arsenite-treated plants, arsenite was the predominant species in the xylem sap, accounting for 93–98% of the total As. A portion of arsenate taken up by roots (30–40% of root As) was reduced to arsenite rapidly. The majority ( c. 80%) of As in fronds was arsenite. Phosphate inhibited arsenate uptake, but not As translocation. More As was translocated to fronds in the arsenite-treated than in the arsenate-treated plants. There was little arsenite efflux from roots to the external solution. • Roots are the main location of arsenate reduction in P. vittata. Arsenite is highly mobile in xylem transport, possibly because of efficient xylem loading, little complexation with thiols in roots, and little efflux to the external medium. [ABSTRACT FROM AUTHOR]

The glycogen synthase gene (GYS1), which encodes the rate-limiting enzyme for glycogen synthesis of skeletal muscle, is a promising candidate gene for traits related to skeletal muscle in pigs. In this study, a G/A single nucleotide polymorphism inGYS1intron 7 detected as aFokI PCR-restriction fragment length polymorphism (PCR-RFLP) showed allele frequency differences among five Chinese indigenous pig breeds and three western commercial pig breeds. Linkage analysis assigned the geneGYS1to marker intervalSW1302– SW1473on SSC6 in a three-generation Meishan X Large White reference family. The results of association analysis and interval mapping suggested that theFokI PCR-RFLP polymorphism might be linked with the quantitative trait loci affecting carcass traits detected on SSC6 in the F2 intercross pedigree. The reverse transcriptase-polymerase chain reaction revealed that the porcineGYS1gene was expressed in spleen, lung, liver, kidney, small intestine, skeletal muscle, heart and stomach, with the highest expression in skeletal muscle. [ABSTRACT FROM AUTHOR]

LIM domain proteins are important regulators of the growth, determination and differentiation of cells. Four-and-a-half LIM-only protein 3 (FHL3) is a type of LIM-only protein that contains four tandemly repeated LIM motifs with an N-terminal single zinc finger (half LIM motif). In this study, we have determined the complete coding sequence of pig FHL3 which encodes a 280 amino acid protein. The coding region of the pig FHL3 gene is organized in five exons and spans an approximately 2.1-kb genomic region. Comparative sequencing of six pig breeds revealed three single nucleotide polymorphisms (SNPs) within exon 2 of which an A→G substitution at position 313 changes a codon for arginine into a codon for glycine. The substitution was situated within a PstI recognition site and developed as a PCR-RFLP marker for further use in population variation investigations and association analysis. The A/G polymorphism was segregating only in Landrace pigs. Association studies of the FHL3 polymorphism with carcass traits provided preliminary evidence that the PstI PCR-restriction fragment length polymorphism (RFLP) genotype may be associated with variation in several carcass traits of interest for pig breeding. Further investigations in more Landrace pigs are needed to confirm this. [ABSTRACT FROM AUTHOR]