ABSTRACT
Using the cDNA-AFLP method, we have isolated a transcript-derived fragment (TDF) which shows a differential expression pattern during tuber organogenesis of Solanum tuberosum L. The TDF was used to isolate a cDNA clone carrying a 1.5 kb insert and potentially coding for a 32.5 kDa peptide which, by homology, represents a potato homologue of an alpha-snap gene and has been designated Stsnap. Northern analysis showed that the Stsnap gene is expressed in actively dividing tissues throughout the potato plant. Analysis of genomic DNA from potato revealed that the Stsnap gene is likely to be a single-copy gene. The expression of antisense Stsnap cDNA under the control of the CaMV 35S promoter results in plants with an altered morphology such as curled leaves. Several of these transgenic lines also display cellular and developmental abnormalities with distinct changes in assimilate transport including accumulation of starch and soluble sugars in source leaves. We argue that these findings are consistent with the hypothetical function of the StSNAP gene product in vesicle targeting and fusion during plant development.
Subject(s)
Carrier Proteins/genetics , DNA, Antisense/genetics , Membrane Proteins/genetics , Solanum tuberosum/genetics , Vesicular Transport Proteins , Amino Acid Sequence , Blotting, Northern , Blotting, Southern , DNA, Complementary/chemistry , DNA, Complementary/genetics , DNA, Plant/genetics , DNA, Recombinant/genetics , DNA, Recombinant/metabolism , Gene Dosage , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Molecular Sequence Data , Phenotype , Plants, Genetically Modified/genetics , Plants, Genetically Modified/growth & development , Plants, Genetically Modified/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Solanum tuberosum/growth & development , Solanum tuberosum/metabolism , Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins , Tissue DistributionABSTRACT
This paper describes a new method for estimating reference ranges of 21 frequently performed laboratory tests utilizing routine test results of selected hospital patients. Computer programs perform the selection of patient records and the statistical analysis. The patient selection criteria of (1) short hospital stay and (2) short laboratory record provide a data base rich in normal results. The statistical program excludes records with excessive variation, and in repeated data-exclusion passes through the data base progressively narrows the range of acceptability. The decision to exclude a record is based on the "pooled variation." The average value of the "pooled variation" increases as the range is narrowed. This approach insures that the process stops after a few passes, and the most consistent data remain included in the calculation of reference ranges. Statistical properties of the data sets, as well as comparison with normal ranges for healthy subjects and review of 560 clinical charts, support the idea that serviceable reference ranges are obtained. The method is suitable for monitoring the reference ranges of the laboratory at frequent intervals.