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T Roscoe

Publications and source records attributed to T Roscoe.

8 recordsLinked to original sources

Characterisation of complementary DNAs from the expressed sequence tag analysis of life cycle stages of Laminaria digitata (Phaeophyceae).

Laminariales (Phaeophyceae, Heterokonta) are characterised by a heteromorphic digenetic life cycle with a filamentous, microscopic gametophyte and a highly evolved, macroscopic sporophyte. With the ultimate goal of comparing gene expression in each life cycle stage, complementary DNA libraries were constructed from sporophytes and gametophytes of Laminaria digitata. A set of ca. 500 expressed sequence tags (EST) was generated from each life history phase, by single-run partial sequencing of randomly picked cDNA clones. Comparison of the EST deduced amino acid sequences with database protein sequences assigned a putative identity for 39% of the 412 gametophyte clones and 48% of the 493 sporophyte clones sequenced thus far. These data represent more than 152 different proteins now probably identified in L. digitata. Several of those newly identified proteins are of interest to our understanding of the molecular physiology of kelps, for example their carbon-concentrating mechanisms, cell wall biosynthesis and halogen metabolism. EST analysis also confirmed that genes with long 3'-UTRs are widespread in Laminariales and the study of 5'-UTRs allowed the identification of a Kozak consensus sequence, c(A/C)A(A/C)CAUGGc(G/T). Several potential developmentally regulated differences in gene expression are discussed.

Algal Proteins↗

Enzymic activities and gene expression of enzymes of the acyl-CoA elongase during rapeseed development.

Enzymic activities and gene expression of oleoyl-CoA elongase were studied during seed development using two different rapeseed cultivars, high-erucic-acid rapeseed (HEAR) and low-erucic-acid rapeseed (LEAR). The overall elongase activities were maximal in HEAR between the fourth and eighth weeks after pollination (WAP) and absent in LEAR. The 3-ketoacyl-CoA synthase (condensing enzyme, CE) mRNA levels and the developmental profiles in the two cultivars were different since maximal expression levels were detected in HEAR and LEAR at WAP 4 and WAP 6, respectively. Anti-CE antibodies revealed two proteins of 60 and 67 kDa in both cultivars and an additional reacting protein of 57 kDa in HEAR.

Acyl-Carrier Protein S-Malonyltransferase↗