Molecular genetic mapping of the <Emphasis Type="Italic">sy1</Emphasis> and <Emphasis Type="Italic">sy9</Emphasis> asynaptic genes in rye (<Emphasis Type="Italic">Secale cereale</Emphasis> L.) using microsatellite and isozyme markers

Studies of phenotypical expression of synaptic mutations in combination with the localization of corresponding genes on a genetic map permit individual stages of the meiotic process to be differentiated. Two rye asynaptic genes, sy1 and sy9, were mapped with the use of microsatellite markers (SSR) in the pericentromeric regions of the long chromosome arms 7R and 2R, respectively. The sy9 gene cosegregated with two SSR markers Xscm43 and Xgwm132. The asynaptic gene sy1 was mapped within the interval between the isozyme locus Aat2 and two cosegregating loci Xrems1188 and Xrems1135 that are located at a distance of 0.4 cM proximally and 0.1 cM distally with respect to the gene lous. Possible evolutionary relationships of the mapped genes with homeological loci of the Triticeae species and more distant cereal species, such as maize and rice, are discussed.     

The order of the <Emphasis Type="Italic">bs,Skdh</Emphasis>, and <Emphasis Type="Italic">Aadh1</Emphasis> genes in chromosome 5R of rye <Emphasis Type="Italic">Secale cereale</Emphasis> L.

Segregation analysis was performed in the progenies obtained in analyzing crosses of hybrids of spring and winter accessions of rye Secale cereale L. and wild S. montanum subsp. anatolicum (Grossh.) Tzvel. (syn. S. strictum (J. Presl) J. Presl). The test genes controlled the brittle stem (bs), the allelic variants of aromatic alcohol dehydrogenase (Aadh1) and shikimate dehydrogenase (Skdh), and the growth habit (Vrn1). A linkage was observed in the inheritance of the brittle stem and the aromatic alcohol dehydrogenase and shikimate dehydrogenase alloenzymes. The order of genes was established to be bs-Skdh-Aadh1, and the genetic distances were estimated to be bs-(9.0%)-Skdh, bs-(10.8%)-Aadh1, and Skdh-(5.3%)-Aadh1. The recombination coefficient between the Skdh and Aadh1 genes varied from 2.2 to 18.2%, averaging 5.3%. The growth habit was inherited independently of the bs-Skdh-Aadh1 linkage group.     

Impairment of homologous chromosome synapsis in meiosis in rye <Emphasis Type="Italic">Secale cereale</Emphasis> L. Caused by a recessive mutation of the <Emphasis Type="Italic">sy18</Emphasis> gene

Expression and inheritance of the sy18 mutation causing impairment of synapsis homology were studied. It was established that the abnormal phenotype is determined by a recessive allele of the sy18 gene. Univalents and multivalents are observed in homozygotes for this mutant allele. According to the electron microscopic analysis of synaptonemal complexes in mutants, homologous synapsis occurs together with nonhomologous synapsis. The sy18 gene was found to have no allelism with asynaptic genes sy1 and sy9 and with genes sy10 and sy19 causing, like sy18, disturbances in synapsis homology.     

Proteolysis of <Emphasis Type="Italic">α</Emphasis>-amylase from <Emphasis Type="Italic">Saccharomycopsis fibuligera</Emphasis>: characterization of digestion products

α-Amylase from Saccharomycopsis fibuligera R-64 was successfully purified by butyl Toyopearl hydrophobic interaction chromatography, followed by Sephadex G-25 size exclusion and DEAE Toyopearl anion exchange chromatography. The enzyme has a molecular mass of 54 kDa, as judged by SDS PAGE analysis. Upon tryptic digestion, two major fragments with relative molecular masses of 39 kDa and 10 kDa, which resemble the A/B and C-terminal domains in the homologous Taka-amylase, were obtained and were successfully separated with the Sephadex G-50 size exclusion column. The 39-kDa fragment demonstrated a similar amylolytic activity to that of the undigested enzyme. However, it was found that the K _m value of the 39-kDa fragment was about two-times higher than that of the undigested enzyme. Moreover, thermostability studies showed a lower half-life time for the 39-kDa fragment. These findings suggest that the 39-kDa fragment is the catalytic domain, while the 10-kDa fragment is the C-terminal one, which plays a role in thermostability and starch binding. Although the undigested enzyme is able to act on raw starches at room temperature, with maize starches as the best substrate, neither the undigested enzyme nor the fragments adsorb the tested raw starches. These results propose Saccharomycopsis fibuligera α-amylase as a raw starch-digesting but not adsorbing amylase, with a similar domain organization to that of Taka-amylase A.     

Structural characteristics of the chloroplast <Emphasis Type="Italic">rpS16</Emphasis> intron in <Emphasis Type="Italic">Allium sativum</Emphasis> and related <Emphasis Type="Italic">Allium</Emphasis> species

The intron sequence of chloroplast rpS16 and the secondary structure of its pre-mRNA were characterized for the first time in 26 Allium sativum accessions of different ecologo-geographical origins and seven related Allium species. The boundaries and main stem-loop consensus sequences were identified for all six domains of the intron. Polymorphism was estimated for the total intron and its regions. The structural regions of the rpS16 intron proved to be heterogeneous for mutation rate and spectrum. Mutations were most abundant in domains II and IV, and transition predominated in domains I, III, V, and VI. In addition to structural elements and motifs typical for group IIB introns, several Allium-specific micro- and macrostructural mutations were revealed. A 290-bp deletion involving domains III and IV and part of domain V was observed in A. altaicum, A. fistulosum, and A. schoenoprasum. Several indels and nucleotide substitutions were found to cause a deviation of the pre-mRNA secondary structure from the consensus model of group II introns.     

<Emphasis Type="Italic">Bacillus anthracis</Emphasis>, <Emphasis Type="Italic">Francisella tularensis</Emphasis> and <Emphasis Type="Italic">Yersinia pestis</Emphasis>. The most important bacterial warfare agents — <Emphasis Type="Italic">review</Emphasis>

There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes: Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed.     

QTLs for resistance to preharvest sprouting in rye (<Emphasis Type="Italic">Secale cereale</Emphasis> L.)

Grain quality of rye is often negatively affected by sprouting - a complex trait with a poorly understood genetic background and strong interaction with weather conditions. The aim of this report was to detect the main quantitative trait loci (QTLs) underlying preharvest sprouting resistance in rye, measured as a percentage of sprouted kernels after spraying spikes with water for 7 days. Simple and composite interval mapping, carried out in 3 environments on 94 F3 and F4 families of the cross between sprouting-susceptible (541) and sprouting-resistant (Ot1-3) inbred lines, revealed 5 QTLs located on chromosome arms 1RL, 2RL, 5RL, 6RL and 7RL. The significance of these QTLs was additionally proved by disruptive selection carried out on 5000 F2 plants of the 541 x Ot1-3 cross and continued to the F5 generation of recombinant inbred lines (RIL), which strongly affected allele frequencies at linked marker loci. Resistance to preharvest sprouting showed dominant inheritance except for QPhs.uas-7R.1 (recessive) and QPhs.uas-1R.1 (additive). Results of the present study suggest that introgression of 4-5 QTLs, identified in line Ot1-3, should substantially reduce sprouting risk in rye varieties.     

Development of an <Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated transformation protocol for the tree-legume <Emphasis Type="Italic">Leucaena leucocephala</Emphasis> using immature zygotic embryos

The tree-legume Leucaena leucocephala (leucaena) is used as a perennial fodder because of its fast-growing foliage, which is high in protein content. The use of leucaena as a fodder is however restricted due to the presence of the toxin mimosine. Improvements in the nutritional contents as well as other agronomic traits of leucaena can be accomplished through genetic transformation. The objective of this research was to develop a transformation protocol for leucaena using phosphinothricin resistance as the plant selectable marker. Explants obtained from immature zygotic embryos infected with the Agrobacterium tumefaciens strain C58C1 containing the binary plasmid pCAMBIA3201 produced four putative transformed leucaena plants. Transformation was confirmed by PCR, RT-PCR, Southern blot, Western analyses, GUS-specific enzyme activity and herbicide leaf spraying assay. A transformation efficiency of 2% was established using this protocol.     

The isolation and analysis of a soybean <Emphasis Type="Italic">CO</Emphasis> Homologue <Emphasis Type="Italic">GmCOL10</Emphasis>

The CONSTANS (CO) gene is a key regulator of the response to photoperiod in the model plant Arabidopsis thaliana, and its homologues are present in many plant species. We describe here the isolation of the CO homologue for zinc finger protein gene GmCOL10 (Glycine max CONSTANS-Like 10) from the soybean cultivar Kennong18. Sequence comparisons showed that the closest A. thaliana gene to GmCOL10 is COL5. The expression of GmCOL10 was regulated in a circadian manner, especially under short-day conditions. The expression of GmCOL10 was concentrated in vegetative organs, and in particular in the unifoliolates and cotyledons. An analysis of subcellular localization found GmCOL10 in the nucleus. Our data suggested that GmCOL10 was not related to the photoperiodic pathway of floral transition as Arabidopsis CO does.     

<Emphasis Type="Italic">Hyptis maya</Emphasis>, a new species of <Emphasis Type="Italic">Lamiaceae</Emphasis> from Belize,Central America,and the closely related <Emphasis Type="Italic">H. lanceolata</Emphasis>

A new species of Lamiaceae from Belize: Hyptis maya is described and illustrated. It is closely related to the more widespread H. lanceolata Poir., with which it is compared.     

Interaction of <Emphasis Type="Italic">Bdellovibrio bacteriovorus</Emphasis> with bacteria <Emphasis Type="Italic">Campylobacter jejuni</Emphasis> and <Emphasis Type="Italic">Helicobacter pylori</Emphasis>

Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection and public health is discussed.     

Frequencies of the <Emphasis Type="Italic">DRB1</Emphasis>, <Emphasis Type="Italic">DQA1</Emphasis>, <Emphasis Type="Italic">DQB1</Emphasis> and <Emphasis Type="Italic">TNFA</Emphasis> alleles in immigrant population of west Siberia

Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined.     

Habitat,density, and spatial distribution of <Emphasis Type="Italic">Rivulus giarettai</Emphasis> (<Emphasis Type="Italic">Actinopterygii</Emphasis>, <Emphasis Type="Italic">Cyprinodontiformes</Emphasis>) in southeastern Brazil

We present data on the habitat, density, and spatial distribution of Rivulus giarettai, and discuss some biotic and abiotic variables related to its abundance in Free Flowing Waters (FFW) and Dam Reservoirs (DR) in palm grove (Mauritia flexuosa) marshes (Veredas) in Uberlandia, Minas Gerais, southeastern Brazil. The mean density (individuals/plot) of R. giarettai was about 13 times higher in FFW than in DR. In FFW, the density of R. giarettai was highest at intermediate amounts of substrate (plant mass) and it was positively rank-correlated with the depth, and the number of arthropods. Individuals occurred in an aggregated distribution. The aggregated pattern could be related to a concentration of individuals in microhabitats neither too much exposed nor completely saturated by plants. R. giarettai was relatively abundant and tolerant to slight man-made habitat modifications. Damming appeared to be especially problematic by negatively affecting its density.     

Isolation of <Emphasis Type="Italic">madA</Emphasis> homologs in <Emphasis Type="Italic">Pilobolus crystallinus</Emphasis>

Pilobolus crystallinus shows unique photoresponses at various growing stages. cDNAs for putative photoreceptors were cloned from this fungus. Three genes named pcmada1, pcmada2, and pcmada3 were identified from the PCR fragments, and amplified with degenerated primers for the LOV domain, which is conserved in many blue-light receptors. Deduced amino acid sequences for PCMADA1, PCMADA2, and PCMADA3 had one light-oxygen-voltage (LOV)-sensing and two PER-ARNT-SIM (PAS) domains. A zinc finger DNA-binding motif was conserved in the C-terminals of PCMADA1 and PCMADA3. However, PCMADA2 lacked the zinc finger motif. Expression of pcmada1 was suppressed by blue light whereas that of pcmada3 was promoted by blue-light irradiation.     

Curculionid beetles in aborted flower buds and immature fruits of <Emphasis Type="Italic">Ceiba</Emphasis><Emphasis Type="Italic">pentandra</Emphasis> (Bombacaceae)

We determined the incidence of curculionid beetles of the genus Lonchophorus on aborted and not aborted flower buds and developing fruits of the tree Ceiba pentandra in southeastern Costa Rica. Beetle larvae were found in reproductive parts of all trees sampled trees. The frequency of beetle larvae was greater in aborted buds and immature fruits. A positive correlation between larvae development and flower bud development indicates that female oviposition occurred in an early flower developmental stage and time until bud abortion is variable. Weevil herbivory could be considered as one of the main factors that cause flower bud and fruit abortion in C. pentandra.

---

Resumen Determinamos la incidencia de curculiónidos del género Lonchophorus en botones florales y frutos inmaduros tanto abortados como no abortados en el árbol Ceiba pentandra en el SE de Costa Rica. Las larvas de curculiónidos fueron encontradas en todos los árboles muestreados. La frecuencia de larvas fue mayor en botones y frutos abortados. Una correlación positiva entre el desarrollo larval y el desarrollo del botón indica que la oviposición ocurre en una fase temprana de este y que el tiempo hasta el aborto es variable. La herbivoría por larvas de curculiónidos puede ser uno de los factores más importantes en el aborto de botones y frutos inmaduros en C. pentandra.