Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0679427 (myeloblastosis)
 982 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzyme-linked immunosorbent assay (ELISA) for avian leukosis/ sarcoma virus (ALV) group-specific (gs) antigens was used to study the identification of hens which congenitally excrete exogenous ALV. The sensitivity of this assay was compared with that of the phenotypic mixing test (PMT) and the direct complement fixation test (CFT) by testing limiting dilutions of purified avian myeloblastosis virus (AMV), embryo homogenates and albumens. About 0.4 ng/ml of purified AMV protein could be detected by ELISA and 23.8 ng/ml of AMV protein was demonstrable by the CFT. The lowest levels of gs-antigen detection corresponded with about 100 median tissue culture infectious doses (TCID50) of infectious ALV. Albumens and embryos of three White Leghorn flocks and one White Plymouth Rock flock were tested for the presence of avian leukosis virus (ALV) gs-antigens by the complement fixation test (CFT) and the enzyme-linked immunosorbent assay (ELISA) and exogenous ALV employing the phenotypic mixing test (PMT). The highest number of ALV-gs antigen positive samples of egg albumens was obtained by the ELISA. In embryo homogenates prepared from eggs of the four flocks under study 100% scores for gs-antigens were obtained by ELISA. A differentiation between gs-antigens of endogenous and exogenous ALV was made by testing of supernatant fluids after one chick embryo fibroblast passage of the C/E phenotype. Endogenous viral (ev) genes leading to the expression of endogenous ALV gs-antigens were apparently present in practically all chickens of the four flocks under study. Complete endogenous ALV (subgroup E) was detected in embryos (41%) from the White Plymouth Rock grandparent flock, but was not found in embryos of two White Leghorn basic breeder flocks. The results indicate that both flocks of White Leghorn chickens are endowed with ev 3 genes. Circumstantial evidence was obtained for the prevalence of endogenous ALV gs-antigens in albumen samples of eggs from flocks with gs+chf+ and V-E+ phenotype respectively.
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PMID:The use of ELISA for detection of exogenous and endogenous avian leukosis viral antigens in basic breeding flocks. 1876 4

Leaf morphology and the pattern of shoot branching determine to a large extent the growth habit of seed plants. Until recently, the developmental processes that led to the establishment of these morphological structures seemed unrelated. Here, we show that the tomato Trifoliate (Tf) gene plays a crucial role in both processes, affecting the formation of leaflets in the compound tomato leaf and the initiation of axillary meristems in the leaf axil. Tf encodes a myeloblastosis oncoprotein (MYB)-like transcription factor related to the Arabidopsis thaliana LATERAL ORGAN FUSION1 (LOF1) and LOF2 proteins. Tf is expressed in the leaf margin, where leaflets are formed, and in the leaf axil, where axillary meristems initiate. During tomato ontogeny, expression of Tf in young leaf primordia increases, correlating with a rise in leaf dissection (heteroblasty). Formation of leaflets and initiation of axillary meristems can be traced back to groups of pluripotent cells. Tf function is required to inhibit differentiation of these cells and thereby to maintain their morphogenetic competence, a fundamental process in plant development. KNOTTED1-LIKE proteins, which are known regulators in tomato leaf dissection, require Tf activity to exert their function in the basal part of the leaf. Similarly, the plant hormone auxin needs Tf activity to initiate the formation of lateral leaflets. Thus, leaf dissection and shoot branching rely on a conserved mechanism that regulates the morphogenetic competence of cells at the leaf margin and in the leaf axil.
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PMID:Trifoliate encodes an MYB transcription factor that modulates leaf and shoot architecture in tomato. 2334 95