Production of 5-methoxypodophyllotoxin in cell suspension cultures of Linum flavum L.

Cell suspension cultures of Linum flavum L., routinely grown on a NAA-containing medium, accumulated low levels of the phenylpropanoid-derived lignan 5-methoxypodophyllotoxin (5-MPT), up to 0.004% on a dry weight basis. Feeding experiments with the precursor L-phenylalanine resulted in a 3–5-fold increase in 5-MPT levels, but caused the levels of PAL activity to fall. Treatment of the cultures with the elicitor Nigeran, either alone or in combination with phenylalanine, caused the 5-MPT production to cease, even though PAL activity was rapidly enhanced by these treatments. Transfer of the cultures to NAA-free medium resulted in a 40–50 fold higher level of 5-MPT accumulation, the PAL activity levels being lowered compared to the routinely grown cells. With these more differentiated cultures, phenylalanine feeding and elicitor treatment, both on its own and in combination with the precursor, had no effect on 5-MPT production, even though the PAL activity levels were higher than in the untreated cells. It can be concluded that in lignan-accumulating cultures of L. flavum, PAL activity is nearly always detectable and seems to show a reciprocal relationship with 5-MPT accumulation.Abbreviations 5-MPT 5-methoxypodophyllotoxin - PAL phenylalanine ammonia lyase (EC 4:3:1.5) - NAA naphthaleneacetic acid     

A tomato cDNA inducible by salt stress and abscisic acid: nucleotide sequence and expression pattern

We have characterized a new tomato cDNA, TAS14, inducible by salt stress and abscisic acid (ABA). Its nucleotide sequence predicts an open reading frame coding for a highly hydrophilic and glycine-rich (23.8%) protein of 130 amino acids. Southern blot analysis of tomato DNA suggests that there is one TAS14 structural gene per haploid genome. TAS14 mRNA accumulates in tomato seedlings upon treatment with NaCl, ABA or mannitol. It is also induced in roots, stems and leaves of hydroponically grown tomato plants treated with NaCl or ABA. TAS14 mRNA is not induced by other stress conditions such as cold and wounding. The sequence of the predicted TAS14 protein shows four structural domains similar to the rice RAB21, cotton LEA D11 and barley and maize dehydrin genes.     

A new species of Lernanthropus De Blainville, 1822 (Copepoda: Lernanthropidae) parasitic on Menticirrhus ophicephalus (Jenyns) (Teleostei: Sciaenidae) from the Peruvian coast

Lernanthropus huamani n. sp. (Copepoda: Lernanthropidae), a parasite of the Peruvian sciaenid fish Menticirrhus ophicephalus (Jenyns), is described and illustrated. The new species differs from all other species of Lernanthropus by a combination of characters, including the dorsal plate, legs and other appendages. L. guacoldae Villalba & Fernández, 1984 is considered a synonym of L. pacificus Oliva & Duran, 1982.     

Isozyme analysis of Galaxias species (Teleostei: Galaxiidae) from the Taieri River, South Island, New Zealand: a species complex revealed

We examined genetic differentiation among 23 samples of non-migratory river galaxias from 17 streams in the Taieri River system, South Island, New Zealand. Four major genetic types were found, two of which occur in narrow sympatry in one location. These were compared with topotypical material representing Galaxias anomalus from the Clutha system (Otago) and G. vulgaris from the Waimakariri system (Canterbury) in order to establish identity. Morphological examination of these four major genetic types revealed consistent concomitant differences. The results suggest that there are at least three species of river galaxias in the Taieri system: G. anomalus, G. vulgaris and at least one previously undescribed species. We propose that the genetic structuring and subsequent speciation of this group has been promoted by the absence of the marine juvenile phase that is found in five other members of the genus native to New Zealand. This structuring may be exacerbated by population fragmentation over the last century owing to the negative influence of introduced trout. The phylogenetic diversity within the river system mirrors the diverse flora and invertebrate fauna of the region, and has conservation implications that parallel those resulting from our improved knowledge of the New Zealand herpetofauna through the application of genetic analysis.     

Xp-duplications with and without sex reversal

Duplications in Xp including the DSS (dosage sensitive sex reversal) region cause male to female sex reversal. We investigated two patients from families with Xp duplications. The first case was one of two sisters with karyotype 46,XY, der(22), t(X;22)(p11.3;p11)mat and unambiguous female genitalia. The living sister was developmentally retarded, and showed multiple dysmorphic features and an acrocallosal syndrome. The second case was a boy with a maternally inherited direct duplication of Xp21.3-pter with the breakpoint close to the DSS locus. He had multiple abnormalities and micropenis, but otherwise unambiguous male genitalia. We performed quantitative Southern blot analysis with probes from Xp22.13 to p21.2 to define the duplicated region. Clinical, cytogenetic, and molecular data from both patients were compared with those of previously reported related cases. A comparison of the extragenital symptoms revealed no differences between patients with or without sex reversal. In both cases, the symptoms were non-specific. Among 22 patients with a duplication in Xp, nine had unambiguous female genitalia and a well-documented duplication of the DSS region. Two patients with duplication of DSS showed ambiguous external genitalia. From these data, we conclude that induction of testicular tissue may start in these patients, but that the type of genitalia depends on the degree of subsequent degeneration by a gene in DSS.     

Biflavonoid differentiation in sixBartramia species (Bartramiaceae,Musci)

The occurrence of eight biflavones belonging to the biluteolin series, the apigenin-luteolin series and the 2,3-dihydro-biluteolin series, and one monomeric flavone with an acid group, was investigated in six taxa ofBartramia with emphasis on sect.Ithyphyllae. The variation of biflavone profiles contributes to the characterization of theBartramia species studied; substitution patterns signalize relevance also on the sectional level. Based upon the flavonoid composition,Bartramia afro-ithyphylla is suggested to be transferred from sect.Ithyphyllae to sect.Bartramia of the genusBartramia.     

Regulation and functional significance of phospholipase D in myocardium

There is now clear evidence that receptor-dependent phospholipase D is present in myocardium. This novel signal transduction pathway provides an alternative source of 1,2-diacylglycerol, which activates isoforms of protein kinase C. The members of the protein kinase C family respond differently to various combinations of Ca²⁺, phosphatidylserine, molecular species of 1,2-diacylglycerol and other membrane phospholipid metabolites including free fatty acids. Protein kinase C isozymes are responsible for phosphorylation of specific cardiac substrate proteins that may be involved in regulation of cardiac contractility, hypertrophic growth, gene expression, ischemic preconditioning and electrophysiological changes. The initial product of phospholipase D, phosphatidic acid, may also have a second messenger role. As in other tissues, the question how the activity of phospholipase D is controlled by agonists in myocardium is controversial. Agonists, such as endothelin-1, atrial natriuretic factor and angiotensin 11 that are shown to activate phospholipase D, also potently stimulate phospholipase C- in myocardium. PMA stimulation of protein kinase C inactivates phospholipase C and strongly activates phospholipase D and this is probably a major mechanism by which agonists that promote phosphatidyl-4,5-bisphosphate hydrolysis secondary activate phosphatidylcholine-hydrolysis. On the other hand, one group has postulated that formation of phosphatidic acid secondary activates phosphatidyl-4,5-bisphosphate hydrolysis in cardiomyocytes. Whether GTP-binding proteins directly control phospholipase D is not clearly established in myocardium. Phospholipase D activation may also be mediated by an increase in cytosolic free Ca²⁺ or by tyrosine-phosphorylation.     

Biotransformation of monoterpenes and sesquiterpenes by cell suspension cultures of Achillea millefolium L. ssp. millefolium

The transformation capacity of Achillea millefolium L. ssp. millefolium (yarrow) cell suspension cultures was investigated using geraniol (50mg/l) and borneol, menthol, thymol and farnesols (25mg/l) as substrates. Apart from converting these substrates into several biotransformation products, the cell suspension cultures were also able to glycosylate both the substrates and the biotransformation products. aa]Key Words bb]Achillea millefolium L. ssp. millefolium bb]Yarrow bb]Compositae bb]Biotransformation bb]Glycosylation bb]Geraniol bb]Borneol bb]Menthol bb]Thymol bb]Farnesols