Precise location of breakpoints in a frequent reciprocal translocation between chromosomes 11 and 22

One of the most frequent chromosomal translocations in human beings is 11q/22q, which results in the "partial trisomy of 22q syndrome." However, the breakpoint on the long arms of chromosomes 11 and 22 is still a matter of controversy. In the present study, we have used chromosomes from lymphocytes of a neonate who happened to have this classical abnormality, and by R-banding prometaphase chromosomes with acridine orange it has been possible to establish that the translocation between chromosomes 11 and 22 resulted from 3:1 meiotic maternal nondisjunction. A detailed analysis of the chromosome regions involved in this translocation revealed that the breakpoints on chromosomes 11 and 22 were at 11q23.3 and 22q11.1, respectively.     

Terfezia disappears from the American truffle mycota as two new genera and Mattirolomyces species emerge

Reexamination and molecular phylogenetic analyses of American Terfezia species and Mattirolomyces tiffanyae revealed that their generic assignments were wrong. Therefore we here propose these combinations: Mattirolomyces spinosus comb. nov. (≡ Terfezia spinosa), Stouffera longii gen. & comb. nov. (≡ Terfezia longii) and Temperantia tiffanyae gen. & comb. nov. (≡ Mattirolomyces tiffanyae). In addition we describe a new species, Mattirolomyces mexicanus spec. nov. All species belong to the Pezizaceae. Based on these results Terfezia is not known from North America, Mattirolomyces is represented by two species and two new monotypic genera are present.     

Proteomic Study of Low-Temperature Responses in Strawberry Cultivars (Fragaria x ananassa) That Differ in Cold Tolerance

To gain insight into the molecular basis contributing to overwintering hardiness, a comprehensive proteomic analysis comparing crowns of octoploid strawberry (Fragaria × ananassa) cultivars that differ in freezing tolerance was conducted. Four cultivars were examined for freeze tolerance and the most cold-tolerant cultivar ('Jonsok') and least-tolerant cultivar ('Frida') were compared with a goal to reveal how freezing tolerance is achieved in this distinctive overwintering structure and to identify potential cold-tolerance-associated biomarkers. Supported by univariate and multivariate analysis, a total of 63 spots from two-dimensional electrophoresis analysis and 135 proteins from label-free quantitative proteomics were identified as significantly differentially expressed in crown tissue from the two strawberry cultivars exposed to 0-, 2-, and 42-d cold treatment. Proteins identified as cold-tolerance-associated included molecular chaperones, antioxidants/detoxifying enzymes, metabolic enzymes, pathogenesis-related proteins, and flavonoid pathway proteins. A number of proteins were newly identified as associated with cold tolerance. Distinctive mechanisms for cold tolerance were characterized for two cultivars. In particular, the 'Frida' cold response emphasized proteins specific to flavonoid biosynthesis, while the more freezing-tolerant 'Jonsok' had a more comprehensive suite of known stress-responsive proteins including those involved in antioxidation, detoxification, and disease resistance. The molecular basis for 'Jonsok'-enhanced cold tolerance can be explained by the constitutive level of a number of proteins that provide a physiological stress-tolerant poise.     

The calcium-binding activity of a vacuole-associated,dehydrin-like protein is regulated by phosphorylation

A vacuole membrane-associated calcium-binding protein with an apparent mass of 45 kD was purified from celery (Apium graveolens). This protein, VCaB45, is enriched in highly vacuolate tissues and is located within the lumen of vacuoles. Antigenically related proteins are present in many dicotyledonous plants. VCaB45 contains significant amino acid identity with the dehydrin family signature motif, is antigenically related to dehydrins, and has a variety of biochemical properties similar to dehydrins. VCaB45 migrates anomalously in sodium dodecyl sulfate-polyacrylamide gel electrophoresis having an apparent molecular mass of 45 kD. The true mass as determined by matrix-assisted laser-desorption ionization time of flight was 16.45 kD. VCaB45 has two characteristic dissociation constants for calcium of 0.22 +/- 0.142 mM and 0.64 +/- 0.08 mM, and has an estimated 24.7 +/- 11.7 calcium-binding sites per protein. The calcium-binding properties of VCaB45 are modulated by phosphorylation; the phosphorylated protein binds up to 100-fold more calcium than the dephosphorylated protein. VCaB45 is an "in vitro" substrate of casein kinase II (a ubiquitous eukaryotic kinase), the phosphorylation resulting in a partial activation of calcium-binding activity. The vacuole localization, calcium binding, and phosphorylation of VCaB45 suggest potential functions.     

Sex preselection of sٍheep embryo by altering the minerals of maternal nutrition

Several methods have been conducted for embryo sex preselection, which includes X- and Y- sperm separation, changing the pH of the female reproductive tract, time of mating before or after ovulation, and feeding formula, such as altering the presence of minerals in diet content before breeding may affect the embryo sex preselection ratio. In this study, three food formulas to feed female sheep were created with the cooperation of the Arabian Agricultural Services Company (Arasco). Ewes were fed with modified food formulas for one month before mating with males. The first group (A) (30 ewes), modified for male embryo gender preselection, were fed a diet with an increased percentage of the minerals Na⁺, K^+, and P^-. The second group (B) (30 ewes), modified for female sex preselection, were fed a diet with an increased percentage of the minerals Ca⁺⁺ and Mg⁺⁺. The third (control) group (C) (30 ewes) were fed the regular (Wafi) food formula. Our results showed no significant differences were in mean body weights between the three groups at the end of the feeding period. The results of different feeding formulas on mineral serum blood samples of ewes showed an increase in Na⁺, K^+, and Cl^- ions in the serum of group (A) compared to the other groups (B and C). The concentration of Na⁺ in the serum of group (A) was significantly (P < 0.05) higher than group (C). The concentration of Cl^- ions in serum samples of ewes in group (A) was significantly higher than group (C) and group (B) (P < 0.05). The role of maternal feeding on embryo sex preselection shows that the pregnancy rate of animals in group (A) was 73.33%. Group (A) birthed 17 males and 5 females (77.27% and 22.72%, respectively). The pregnancy rate in group (B) was 70%. Group (B) birthed 6 males (27.27%) and 16 females (72.72%). Finally, the control group (C) had a pregnancy rate of 76.66%. They birthed 13 males (54.41%) and 11 females (44.83%). The results of our study confirm that altering the percentage of minerals in the maternal diet plays a role in sex preselection in sheep, which agree with other mammalian studies in rats and mice. Thus, the result of this study can help farmers to manage their breeding. We recommend that more studies on the relationship between minerals in the diet should be conducted for other spices and human sex preselection.     

Mutations in SUPPRESSOR OF VARIEGATION1, a factor required for normal chloroplast translation, suppress var2-mediated leaf variegation in Arabidopsis

The Arabidopsis thaliana yellow variegated2 (var2) mutant is variegated due to lack of a chloroplast FtsH-like metalloprotease (FtsH2/VAR2). We have generated suppressors of var2 variegation to gain insight into factors and pathways that interact with VAR2 during chloroplast biogenesis. Here, we describe two such suppressors. Suppression of variegation in the first line, TAG-FN, was caused by disruption of the nuclear gene (SUPPRESSOR OF VARIEGATION1 [SVR1]) for a chloroplast-localized homolog of pseudouridine (Psi) synthase, which isomerizes uridine to Psi in noncoding RNAs. svr1 single mutants were epistatic to var2, and they displayed a phenotypic syndrome that included defects in chloroplast rRNA processing, reduced chloroplast translation, reduced chloroplast protein accumulation, and elevated chloroplast mRNA levels. In the second line (TAG-IE), suppression of variegation was caused by a lesion in SVR2, the gene for the ClpR1 subunit of the chloroplast ClpP/R protease. Like svr1, svr2 was epistatic to var2, and clpR1 mutants had a phenotype that resembled svr1. We propose that an impairment of chloroplast translation in TAG-FN and TAG-IE decreased the demand for VAR2 activity during chloroplast biogenesis and that this resulted in the suppression of var2 variegation. Consistent with this hypothesis, var2 variegation was repressed by chemical inhibitors of chloroplast translation. In planta mutagenesis revealed that SVR1 not only played a role in uridine isomerization but that its physical presence was necessary for proper chloroplast rRNA processing. Our data indicate that defects in chloroplast rRNA processing are a common, but not universal, molecular phenotype associated with suppression of var2 variegation.     

Mitochondrial dysfunction contributes to the cytotoxicity of some 3,5-bis(benzylidene)-4-piperidone derivatives in colon HCT-116 cells

The objectives of this study are to investigate the possible ways by which the curcumin analogs 2a and 2b exert their antiproliferative properties. The analogs 2a and 2b have submicromolar IC₅₀ values towards human HCT-116 colon cancer cells but are far less toxic to human non-malignant CRL-1790 colon cells. Both compounds affected a number of mitochondrial functions in HCT-116 cells namely increasing the intracellular concentrations of reactive oxygen species, inhibiting oxygen consumption and decreasing the mitochondrial membrane potential. These molecules also produced swelling of isolated rat liver mitochondria, supporting a mitochondrial mechanism of cytotoxicity. Both compounds reacted with glutathione in the presence of glutathione S-transferase π and hence they may be classified as thiol alkylators.     

Mapping and validation of powdery mildew resistance loci from spring wheat cv. Naxos with SNP markers

Powdery mildew, caused by Blumeria graminis f.sp. tritici, is a major wheat disease in maritime and temperate climates. Breeding for race-non-specific or partial resistance is a cost-effective and environmentally friendly disease control strategy. The German spring wheat cultivar Naxos has proven to be a good source for partial resistance to powdery mildew. The objectives of the present study were to map the resistance loci in Naxos with use of high-density SNP markers in the Shanghai3/Catbird x Naxos inbred line population and validate the results in a different genetic background; Soru#1 x Naxos. Both populations were genotyped with the Illumina iSelect 90K wheat chip, and integrated linkage maps developed by inclusion of previously genotyped SSR and DArT markers. With the new linkage maps, we detected a total of 12 QTL for powdery mildew resistance in Shanghai3/Catbird x Naxos, of which eight were derived from Naxos. Previously reported QTL on chromosome arms 1AS and 2BL were more precisely mapped and the SNP markers enabled discovery of new QTL on 1AL, 2AL, 5AS and 5AL. In the Soru#1 x Naxos population, four QTL for powdery mildew resistance were detected, of which three had resistance from Naxos. This mapping verified the 1AS and 2AL QTL detected in Shanghai3/Catbird x Naxos, and identified a new QTL from Naxos on 2BL. In conclusion, the improved linkage maps with SNP markers enabled discovery of new resistance QTL and more precise mapping of previously known QTL. Moreover, the results were validated in an independent genetic background.     

Ion binding properties of the dehydrin ERD14 are dependent upon phosphorylation

The ERD14 protein (early response to dehydration) is a member of the dehydrin family of proteins which accumulate in response to dehydration-related environmental stresses. Here we show the Arabidopsis dehydrin, ERD14, possesses ion binding properties. ERD14 is an in vitro substrate of casein kinase II; the phosphorylation resulting both in a shift in apparent molecular mass on SDS-PAGE gels and increased calcium binding activity. The phosphorylated protein bound significantly more calcium than the nonphosphorylated protein, with a dissociation constant of 120 microm and 2.86 mol of calcium bound per mol of protein. ERD14 is phosphorylated by extracts of cold-treated tissues, suggesting that the phosphorylation status of this protein might be modulated by cold-regulated kinases or phosphatases. Calcium binding properties of ERD14 purified from Arabidopsis extracts were comparable with phosphorylated Escherichia coli-expressed ERD14. Approximately 2 mol of phosphate were incorporated per mol of ERD14, indicating a minimum of two phosphorylation sites. Western blot analyses confirmed that threonine and serine are possible phosphorylation sites on ERD14. Utilizing matrix assisted laser desorption ionization-time of flight/mass spectrometry we identified five phosphorylated peptides that were present in both in vivo and in vitro phosphorylated ERD14. Our results suggest that the polyserine (S) domain is most likely the site of phosphorylation in ERD14 responsible for the activation of calcium binding.     

A ddRAD Based Linkage Map of the Cultivated Strawberry,Fragaria xananassa

The cultivated strawberry (Fragaria ×ananassa Duch.) is an allo-octoploid considered difficult to disentangle genetically due to its four relatively similar sub-genomic chromosome sets. This has been alleviated by the recent release of the strawberry IStraw90 whole genome genotyping array. However, array resolution relies on the genotypes used in the array construction and may be of limited general use. SNP detection based on reduced genomic sequencing approaches has the potential of providing better coverage in cases where the studied genotypes are only distantly related from the SNP array’s construction foundation. Here we have used double digest restriction-associated DNA sequencing (ddRAD) to identify SNPs in a 145 seedling F₁ hybrid population raised from the cross between the cultivars Sonata (♀) and Babette (♂). A linkage map containing 907 markers which spanned 1,581.5 cM across 31 linkage groups representing the 28 chromosomes of the species. Comparing the physical span of the SNP markers with the F. vesca genome sequence, the linkage groups resolved covered 79% of the estimated 830 Mb of the F. ×ananassa genome. Here, we have developed the first linkage map for F. ×ananassa using ddRAD and show that this technique and other related techniques are useful tools for linkage map development and downstream genetic studies in the octoploid strawberry.