MAJOR CLADES OF THE ANGIOSPERMS

Abstract— Our knowledge of fundamental angiosperm interrelationships is still very incomplete. The absence of a narrowly circumscribed gymnosperm outgroup, ideally the sister group, makes character evaluation, necessary for a cladistic analysis, difficult. According to current views the superorder Magnoliiflorae with a number of other groups, for example the monocotyledons, may represent a complex of families near the base of the angiosperms. Interrelationships of groups within the monocotyledons are much better understood than those between groups within the dicotyledons. A cladogram of monocotyledon orders based on earlier work by R. Dahlgren, H. T. Clifford, and F. N. Rasmussen is presented. A data matrix for a sample of the angiosperms with 61 characters for 49 taxa, mostly magnoliifloran and related families, is presented. The characters are polarized mainly according to the current view that the primitive angiosperm morphotype is a woody dicotyledon with strobiloid flowers. As an alternative the matrix is adjusted following W. C. Burger's conjecture that the primitive angiosperm was a herbaceous monocotyledon with trimerous flowers. Both matrices were run in a computerized parsimony analysis, resulting in numerous equally parsimonious solutions. This result is illustrative of the great homoplasy in the available character information, and also of how little actually is known about fundamental angiosperm interrelationships or phylogeny.     

Assignment of orthologous relationships among mammalian alpha-globin genes by examining flanking regions reveals a rapid rate of evolution

In order to study the relationships among mammalian alpha-globin genes, we have determined the sequence of the 3' flanking region of the human alpha 1 globin gene and have made pairwise comparisons between sequenced alpha-globin genes. The flanking regions were examined in detail because sequence matches in these regions could be interpreted with the least complication from the gene duplications and conversions that have occurred frequently in mammalian alpha-like globin gene clusters. We found good matches between the flanking regions of human alpha 1 and rabbit alpha 1, human psi alpha 1 and goat I alpha, human alpha 2 and goat II alpha, and horse alpha 1 and goat II alpha. These matches were used to align the alpha-globin genes in gene clusters from different mammals. This alignment shows that genes at equivalent positions in the gene clusters of different mammals can be functional or nonfunctional, depending on whether they corrected against a functional alpha-globin gene in recent evolutionary history. The number of alpha-globin genes (including pseudogenes) appears to differ among species, although highly divergent pseudogenes may not have been detected in all species examined. Although matching sequences could be found in interspecies comparisons of the flanking regions of alpha- globin genes, these matches are not as extensive as those found in the flanking regions of mammalian beta-like globin genes. This observation suggests that the noncoding sequences in the mammalian alpha-globin gene clusters are evolving at a faster rate than those in the beta-like globin gene clusters. The proposed faster rate of evolution fits with the poor conservation of the genetic linkage map around alpha-globin gene clusters when compared to that of the beta-like globin gene clusters. Analysis of the 3' flanking regions of alpha-globin genes has revealed a conserved sequence approximately 100-150 bp 3' to the polyadenylation site; this sequence may be involved in the expression or regulation of alpha-globin genes.      

P48-Triggered transmembrane signaling transduction of human monocytes:mobilization of calcium ion and activation of protein kinase C(PKC)

INTRODUCTI0NThedifferentiati0nofcelIsalongthemonocyte-macr0phagepathwayandthesig-nalsinvo1vedinthesecel1sacquiringtheabilitytokilltum0rcellsarenotfllllyundersto0d.Wehavebeenstudingamoleculewhichappearst0beanimportantmemberofthecytokinenetworkinvo1vedintheregulati0nmonocyteactivation.ThiscytokinetermedP48wasisolatedfr0mthehllmannullcellleukemiacell1ineReh.IthasbeenpurifiedtohomogeneityandfOundtobedistinctfrominterferongamma,col0nystimulatingfactors(CSFs)andTNFalphaalldbeta[1,2].Func-ti…     

Effect of chronic treatment with neuroleptics on the content of 3',5'-cyclic guanosine monophosphate in cerebellar cortex of rats.

Chronic treatment with haloperidol is associated with complete tolerance to the decreasing effect of the neuroleptic on cerebellar cGMP content, vice versa chronic haloperidol causes hypersensitivity to the enhancing effect of apomorphine on cerebellar cGMP. Thus, the administration of 0.5 mg/Kg of haloperidol decreases cerebellar cGMP by 80% in control rats but fails to alter this nucleotide in rats chronically treated with haloperidol (0.5 mg/Kg twice daily for 20 days). A dose of 0.5 mg/Kg of apomorphine enhances cGMP by approximately 25 and 60 percent in control rats and in rats chronically treated with haloperidol, respectively. The results suggest that: a) There is a functional link between striatum and cerebellum; b) Cerebellar cGMP is a sensitive index of the state of activation of striatal dopamine receptors.     

Intracerebral injection of gamma vinyl GABA: Method for measuring rates of GABA synthesis in specific brain regions invivo

In order to obtain an index of the rate of GABA synthesis in different rat brain regions, we examined the rate of accumulation of GABA after irreversible inhibition of GABA-transaminase. Gamma-vinyl-GABA (GVG), a catalytic inhibitor of GABA-transaminase, was microinjected directly into each of four brain areas: superior colliculus (SC), substantia nigra (SN), frontal cortex (CTX) and caudate-putamen (CP). The subsequent rate of GABA accumulation was linear for at least 90 min in all regions, and was found to be 2–3 times higher in the SC and SN than in the CTX and CP. The nerve terminal contribution to the initial rate of GABA accumulation after GVG was determined by comparing values obtained in the intact SN with those obtained in the SN in which the GABAergic afferent terminals had been destroyed. The initial rate of GABA accumulation in the denervated SN was less than one-half of that measured in the intact SN, indicating that, under normal conditions, both nerve-terminal and non-nerve-terminal (perikarya, glia) compartments contribute to the rate of GABA accumulation after GABA-transaminase inhibition. Our results indicate that the intracerebral injection of GVG is a sensitive and reliable method for studying $\text{in}\text{vivo}$ GABA synthesis in brain. Although the rate of GABA accumulation after GVG is sensitive to changes in the nerve terminal compartment, other GABA compartments may also influence these measurements.     

Spatial genetic patterns of Octopus vulgaris Mediterranean populations support the hypothesis of a transitional zone across the Siculo-Tunisian Strait

Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break...     

Synthesis of 2′-Substituted Inosine Analogs via Unusual Masking of the 6-Hydroxyl Group

2′-Modified inosine analogs have been synthesized from 6-chloropurine riboside via 6-dimethylaminopurine or 6-benzyloxypurine intermediates. The dimethylaminopurine intermediate was obtained via an unusually facile dimethylamine transfer from dimethylformamide.

Graphical Abstract: