Trees on networks: resolving statistical patterns of phylogenetic similarities among interacting proteins

Background  

Phylogenies capture the evolutionary ancestry linking extant species. Correlations and similarities among a set of species are mediated by and need to be understood in terms of the phylogenic tree. In a similar way it has been argued that biological networks also induce correlations among sets of interacting genes or their protein products.     

Genetic control of the oil content in Thymus vulgaris L: a case of polymorphism in a biosynthetic chain

Six distinet chemotypes of the mediterranean Thymus vulgaris L. are characterized by differences in the major monoterpenes produced. The nature of the monoterpenes is shown to be controlled by a series of loci. Each locus probably has a dominant and a recessive allele. Epistatic relationships between these loci are interpreted by assuming that terpenes are end products of branches from the same biosynthetic pathway. The most dominant types, which correspond to the monoterpenes produced at the beginning of the chain, show the most important potential genetic diversity. There is good evidence that regulatory genos are involved in this system.     

Genetic mapping of three human homologues of murine t-complex genes localizes TCP10 to 6q27, 15 cM distal to TCP1 and PLG

Human homologues of mouse t-complex genes have been cloned and localized physically to chromosome 6p or 6q. TCP1, TCP10, and PLG are human homologues of genes located in the proximal portion of the t-complex on mouse chromosome 17. We present here results of genetic mapping of these human t-complex homologues previously localized to 6q25-q27, 6q21-q27, and 6q26-q27, respectively, by physical techniques. TCP1 and PLG do not recombine with each other and are separated from TCP10 by about 15 cM, while the corresponding mouse genes are no more than 4 cM apart. Genetic mapping with markers well localized cytogenetically places TCP1 and PLG proximal to TCP10 and localizes the latter to the cytogenetic band 6q27. It is likely that the organization of human t-complex homologues on 6q is similar to that of t haplotypes rather than that of wildtype murine chromosome 17.     

南瓜雌蕊与自花及远缘花粉的相互作用

南瓜柱头表面经去垢剂、蛋白酶及Con A处理后花粉不能萌发或花粉管生长受阻,Con A能专一地与柱头表面结合。柱头块加入培养液可促进花粉萌发。不同的远缘花粉授粉后在雌蕊不同部位受阻。在成熟南瓜雌蕊提取液中检测到血凝活性,凝集素可能参与雌蕊对远缘花粉的抑制。     

Evolution of reproductive systems in the genus Silene

The genus Silene contains both hermaphrodite, gynodioecious and dioecious species, dioecy being represented in three sections of the genus. To locate the events of change of reproductive systems, we compared ITS sequences of 22 species of Silene chosen throughout the whole genus, and four putative outgroup species. Gynodioecy, which is the most common reproductive system within the genus Silene and in closely related genera such as Saponaria and Dianthus, is proposed to be ancestral in the genus. Dioecy has evolved at least twice: once in the section containing S. latifolia, and once in the clade containing S. otites and S. acaulis ssp. bryoides. Evolution towards hermaphroditism, associated with evolution of selfing has also occurred at least twice, in S. gallica and S. comica.     

A centromere-based genetic map of the short arm of human chromosome 6

A genetic map of the short arm of chromosomes 6 (6p) has been constructed with 20 genetic markers that define 16 loci, including a locus at the centromere. The 40 CEPH families and, for 4 loci, 13 additional Utah families were genotyped. All 16 loci form a single linkage group extending from near the telomeric region to the centromere, covering 159 cM (Haldane) on the female map and 94 cM on the male map. Sex differences in recombination frequencies are noted for the 6p map, with an excess occurring in males at the distal end. The genetic order of loci is consistent with their physical localization on 6p. Proximal to the three most distal loci on the map, markers are especially dense, providing an extended region on 6p useful for localizing genes of interest.