An Odorant-Binding Protein Is Abundantly Expressed in the Nose and in the Seminal Fluid of the Rabbit

We have purified an abundant lipocalin from the seminal fluid of the rabbit, which shows significant similarity with the sub-class of pheromone carriers “urinary” and “salivary” and presents an N-terminal sequence identical with that of an odorant-binding protein (rabOBP3) expressed in the nasal tissue of the same species. This protein is synthesised in the prostate and found in the seminal fluid, but not in sperm cells. The same protein is also expressed in the nasal epithelium of both sexes, but is completely absent in female reproductive organs. It presents four cysteines, among which two are arranged to form a disulphide bridge, and is glycosylated. This is the first report of an OBP identified at the protein level in the seminal fluid of a vertebrate species. The protein purified from seminal fluid is bound to some organic chemicals whose structure is currently under investigation. We reasonably speculate that, like urinary and salivary proteins reported in other species of mammals, this lipocalin performs a dual role, as carrier of semiochemicals in the seminal fluid and as detector of chemical signals in the nose.     

Suspensor Length Determines Developmental Progression of the Embryo in Arabidopsis

The first structure that differentiates during plant embryogenesis is the extra-embryonic suspensor that positions the embryo in the lumen of the seed. A central role in nutrient transport has been ascribed to the suspensor in species with prominent suspensor structures. Little is known, however, about what impact the size of the rather simple Arabidopsis (Arabidopsis thaliana) suspensor has on embryogenesis. Here, we describe mutations in the predicted exo-polygalacturonase gene NIMNA (NMA) that lead to cell elongation defects in the early embryo and markedly reduced suspensor length. Mutant nma embryos develop slower than wild-type embryos, and we could observe a similar developmental delay in another mutant with shorter suspensors. Interestingly, for both genes, the paternal allele has a stronger influence on the embryonic phenotype. We conclude that the length of the suspensor is crucial for fast developmental progression of the embryo in Arabidopsis.Annual, self-pollinating weeds such as Arabidopsis (Arabidopsis thaliana) benefit from a short life cycle in their natural ephemeral habitats (Snell and Aarssen, 2005). A rapid progression through embryogenesis is a prerequisite for early seed maturation, and it is therefore not surprising that Arabidopsis sets up its body plan already after a very limited number of cell divisions (Aarssen, 2000; Lau et al., 2012).Arabidopsis embryogenesis starts with the fertilized egg cell, the zygote, which elongates about 3-fold before it divides asymmetrically. The smaller apical cell is the founder of the embryo proper that contributes to most of the later seedling, while the larger basal cell develops into a support structure called the suspensor (Jeong et al., 2011a). The suspensor is formed by a series of transverse cell divisions followed by longitudinal cell expansion forming a stalk-like structure. Only the upper-most suspensor cell, the hypophysis, will contribute to parts of the root meristem, while the rest of the suspensor remains extraembryonic and will cease its growth at the heart stage of the embryo (Yeung and Meinke, 1993). The suspensor is thought to be important for pushing the embryo into the lumen of the seed, where the embryo is surrounded by the nourishing endosperm. In addition, a key function in nutrient and hormone transport to the embryo is assigned to the suspensor (Kawashima and Goldberg, 2010).The Arabidopsis suspensor achieves its maximum length with a minimum number of cells by having a rod-shaped structure built by a single cell file. Although several mutants with distorted or shorter suspensors have been described in Arabidopsis, little is known about what impact suspensor length has on embryo development (Schwartz et al., 1994; Vernon and Meinke, 1994; Lukowitz et al., 2004; Breuninger et al., 2008; Bayer et al., 2009; Jeong et al., 2011b).As in all plant cells, the size and shape of suspensor cells is primarily determined by the elasticity of the cell wall. While rigid cellulose microfibrils determine the direction of cell expansion, it is the pectin matrix that plays a major role in determining the stiffness of the cell wall (Peaucelle et al., 2012). Several pectin-modifying enzymes have been described that modulate the elasticity of the cell wall. Among these, pectin methyl esterases that determine the degree of homogalacturonan methylation seem to be major players (Palin and Geitmann, 2012). Pectin-degrading enzymes such as polygalacturonases (PGs) have been implicated with cell expansion, but their role in this process is much less clear (Hadfield and Bennett, 1998).The pectin-rich middle lamella serves as cement to aid cell adhesion, and it is therefore not surprising that several PG genes are involved in dehiscence and abscission events (Rhee et al., 2003; González-Carranza et al., 2007, 2012; Ogawa et al., 2009). The expression profile of many PG genes correlates temporally and spatially with cell elongation and therefore implies a role in cell expansion (Sitrit et al., 1999). The exact function of PGs during cell elongation is still unclear, and the lack of elongation defects in loss-of-function mutants further complicates matters.Here, we describe mutations in a PG gene, which we called NIMNA (NMA), that severely affect cell elongation in the embryo and suspensor.We demonstrate that embryos with shorter suspensors show a significant delay in development during embryogenesis, possibly caused by reduced access to nutrients from the endosperm. Interestingly, reciprocal crosses reveal an unequal parental contribution to NMA function in cell elongation of the suspensor.     

Opa1 Is Required for Proper Mitochondrial Metabolism in Early Development

Opa1 catalyzes fusion of inner mitochondrial membranes and formation of the cristae. OPA1 mutations in humans lead to autosomal dominant optic atrophy. OPA1 knockout mice lose viability around embryonic day 9 from unknown reasons, indicating that OPA1 is essential for embryonic development. Zebrafish are an attractive model for studying vertebrate development and have been used for many years to describe developmental events that are difficult or impractical to view in mammalian models. In this study, Opa1 was successfully depleted in zebrafish embryos using antisense morpholinos, which resulted in disrupted mitochondrial morphology. Phenotypically, these embryos exhibited abnormal blood circulation and heart defects, as well as small eyes and small pectoral fin buds. Additionally, startle response was reduced and locomotor activity was impaired. Furthermore, Opa1 depletion caused bioenergetic defects, without impairing mitochondrial efficiency. In response to mitochondrial dysfunction, a transient upregulation of the master regulator of mitochondrial biogenesis, pgc1a, was observed. These results not only reveal a new Opa1-associated phenotype in a vertebrate model system, but also further elucidates the absolute requirement of Opa1 for successful vertebrate development.     

Chromosomal Mapping of HSPCB and MYL1 Expressed Abundantly in the Bovine Fetus

Abstract

Chromosomal mapping of expressed sequence tags for HSPCB and MYL1 expressed abundantly in the bovine fetus was performed by analyzing bovine/murine somatic cell hybrid DNAs with polymerase chain reaction (PCR) using primers specific for those 3^′‐untranslated regions. HSPCB and MYL1 were assigned to bovine chromosomes 23 and 2, respectively.     

Growth Arrest Specific 1 (GAS1) Is Abundantly Expressed in the Adult Mouse Central Nervous System

Growth arrest specific 1 (GAS1) is a pleiotropic protein that induces apoptosis and cell arrest in different tumors, but it is also involved in the development of the nervous system and other tissues and organs. This dual ability is likely caused by its capacity to interact both by inhibiting the intracellular signaling cascade induced by glial cell-line derived neurotrophic factor and by facilitating the activity of the sonic hedgehog pathway. The presence of GAS1 mRNA has been described in adult mouse brain, and here we corroborated this observation. We then proceeded to determine the distribution of the protein in the adult central nervous system (CNS). We detected, by western blot analysis, expression of GAS1 in olfactory bulb, caudate-putamen, cerebral cortex, hippocampus, mesencephalon, medulla oblongata, cerebellum, and cervical spinal cord. To more carefully map the expression of GAS1, we performed double-label immunohistochemistry and noticed expression of GAS1 in neurons in all brain areas examined. We also observed expression of GAS1 in astroglial cells, albeit the pattern of expression was more restricted than that seen in neurons. Briefly, in the present article, we report the widespread distribution and cellular localization of the GAS1 native protein in adult mammalian CNS.     

Compositional Characterization and Pyrolysis of Loblolly Pine and Douglas-fir Bark

Two potential biofuel resources, Douglas-fir and Loblolly pine bark, were subjected to extensive chemical and compositional analysis. The barks were initially extracted with dichloromethane, and the resulting extracted compounds were characterized by gas chromatography coupled with mass spectrometric analysis. Characterization of the major bark biocomponents indicated that Douglas-fir and Loblolly pine bark contained 22.5 and 13.2 % tannins, 44.2 and 43.5 % lignin, 16.5 and 23.1 % cellulose, and 7.6 and 14.1 % hemicellulose, respectively. Of particular interest is the high content of tannins and lignin, which make these barks excellent potential precursors for bio-oils and/or other value-added chemicals. ¹³C nuclear magnetic resonance (NMR) was used to characterize the chemical structure of the lignin and tannins. These samples were also analyzed by ³¹P NMR after phosphitylation of the hydroxyl groups in lignin and tannins. The NMR spectral data indicated that the lignin in both barks contained p-hydroxyphenyl (h) and guaiacyl (g) of lignin monomers with an h/g ratio of 10:90 and 22:78 for Douglas-fir and Loblolly pine bark, respectively. Gel permeation chromatography was used to analyze the molecular weight distributions of extracted tannins, isolated cellulose, and ball-milled lignin. The pyrolysis of Douglas-fir and pine bark at 500°C in a tubular reactor generated 48.2 and 45.2 % of total oil, of which the light oil contents are 14.1 and 20.7 % and heavy oil are 34.1 and 24.4 %. Similarly, fast pyrolysis at 375°C yielded 56.1 and 49.8 % of total oil for Douglas-fir and pine bark, respectively.     

Effect of Nitrogen Fertilization and Growth Suppression on Pitch Canker Development on Loblolly Pine Seedlings

One-yr-old loblolly pine seedlings of two half-sib families, grown in sand, were fertilized three times per week with nutrient solution containing 20 μg/ml (low) or 80 μg/ml (high) nitrogen. Nitrogen concentration in the nutrient solution was either constant throughout the experiment, or interehanged after the inoculation of stems or shoots with Fusarium subglutinans, 55 days after initiation of fertilization. Growth was suppressed by a weekly excision of shoots branching from the stem apex. Either high nitrogen nutrition or shoot excision generally enhanced canker elongation on stem inoculated plants; the combination of both was extremely conducive for disease development. With intact plants of family 8–68, interchange of pre-inoculation low nitrogen nutrition with high nitrogen after inoculation enhanced canker elongation and rate of wilt. Nitrogen content varied in wood, bark and needles, as well as with time intervals, but was consistently in accordance with nitrogen level in the nutrient solution. In shoot excised plants, nitrogen content was higher than in the respective treatment without shoot excision. The higher nitrogen nutrient accelerated disease development on inoculated shoots, compared to low nitrogen, on both pine families. With respective treatments, stem cankers were larger and rates of shoots exhibiting lesions or wilt were higher on plants of family 8–68 than on 8–61. It is postulated that the disease enhancing effect associated with higher nitrogen content in stem tissues results from an increased nitrogen availability to the pathogen.     

47个早期人胚胎低丰度表达基因ESTs筛选及结果分析

构建高质量ｃＤＮＡ文库在基因克隆、ｍＲＮＡ差异展示、表达序列标签测序和基因定位等研究中具有十分重要的作用。为了从早期胚胎中分离人类新基因,构建了受精后３周龄的人ｃＤＮＡ文库,用标记的一链ｃＤＮＡ探针对该文库的６５０８个克隆子进行菌落原位杂交,得到１６７７个无任何杂交信号的低丰度表达克隆子,从中随机挑选了４７个进行５′端部分测序,将测序结果与三大基因库进行序列同源性比较,发现１８个克隆（３８．３％）     

The Arabidopsis 1-Aminocyclopropane-1-Carboxylate Synthase Gene 1 Is Expressed during Early Development

The temporal and spatial expression of one member of the Arabidopsis 1-aminocyclopropane-1-carboxylate (ACC) synthase gene family (ACS1) was analyzed using a promoter-[beta]-glucuronidase fusion. The expression of ACS1 is under developmental control both in shoot and root. High expression was observed in young tissues and was switched off in mature tissues. ACS1 promoter activity was strongly correlated with lateral root formation. Dark-grown seedlings exhibited a different expression pattern from light-grown ones. The ACC content and the in vivo activity of ACC oxidase were determined. ACC content correlated with ACS1 gene activity. ACC oxidase activity was demonstrated in young Arabidopsis seedlings. Thus, the ACC formed can be converted into ethylene. In addition, ethylene production of immature leaves was fourfold higher compared to that of mature leaves. The possible involvement of ACS1 in influencing plant growth and development is discussed.     

Ezrin Is Highly Expressed in Early Thymocytes,but Dispensable for T Cell Development in Mice

Background

Ezrin/radixin/moesin (ERM) proteins are highly homologous proteins that function to link cargo molecules to the actin cytoskeleton. Ezrin and moesin are both expressed in mature lymphocytes, where they play overlapping roles in cell signaling and polarity, but their role in lymphoid development has not been explored.

Methodology/Principal Findings

We characterized ERM protein expression in lymphoid tissues and analyzed the requirement for ezrin expression in lymphoid development. In wildtype mice, we found that most cells in the spleen and thymus express both ezrin and moesin, but little radixin. ERM protein expression in the thymus was differentially regulated, such that ezrin expression was highest in immature thymocytes and diminished during T cell development. In contrast, moesin expression was low in early thymocytes and upregulated during T cell development. Mice bearing a germline deletion of ezrin exhibited profound defects in the size and cellularity of the spleen and thymus, abnormal thymic architecture, diminished hematopoiesis, and increased proportions of granulocytic precursors. Further analysis using fetal liver chimeras and thymic transplants showed that ezrin expression is dispensable in hematopoietic and stromal lineages, and that most of the defects in lymphoid development in ezrin^−/− mice likely arise as a consequence of nutritional stress.

Conclusions/Significance

We conclude that despite high expression in lymphoid precursor cells, ezrin is dispensable for lymphoid development, most likely due to redundancy with moesin.     

Rapid and Reliable Differential Display from Minute Amounts of Tissue: Mass Cloning and Characterization of Differentially Expressed Genes from Loblolly Pine Embryos

Performing RNA differential display analysis on small tissue samples is difficult since much RNA, the initial template for the reaction, is lost during conventional isolation procedures. We have developed a rapid method which employs oligo-dT beads to capture mRNA from cell lysates. Subsequent reactions are primed directly from the beads, thus RT and PCR reactions can be completed within a few hours of tissue harvest. This approach allows us to perform differential display on a single pine embryo. We describe strategies for distinguishing classes of co-migrating bands excised from differential display gels and outline a PCR-based method for confirming differential expression of large numbers of cloned bands in cases where RNA quantities are limiting.     

Specifically Expressed Genes of the Nematode Bursaphelenchus Xylophilus Involved with Early Interactions with Pine Trees

As the causal agent of pine wilt disease (PWD), the pine wood nematode (PWN), Bursaphelenchus xylophilus, causes huge economic losses by devastating pine forests worldwide. However, the pathogenesis-related genes of B. xylophilus are not well characterized. Thus, DNA microarrays were used to investigate differential gene expression in PWN where Pinus thunbergii was inoculated with nematodes, compared with those cultured on Botrytis cinerea. The microarrays comprised 31121 probes, 1310 (4.2%) of which were differentially regulated (changes of >2-fold, P < 0.01) in the two growth conditions. Of these 1310 genes, 633 genes were upregulated, whereas 677 genes were downregulated. Gene Ontology (GO) categories were assigned to the classes Cellular Component, Molecular Function, and Biological Process. The comparative gene expression analysis showed that a large number of the pathogenesis-related genes of B. xylophilus, such as pectate lyase genes, cytochrome P450s, UGTs, and ABC transporter genes, were highly expressed when B. xylophilus infected P. thunbergii. Annotation analysis indicated that these genes contributed to cell wall degradation, detoxification, and the reproduction process. The microarray results were validated using quantitative RT-PCR (qRT-PCR). The microarray data confirmed the specific expression of B. xylophilus genes during infection of P. thunbergii, which provides basic information that facilitates a better understanding of the molecular mechanism of PWD.     

Activity of Some Hydrolytic Enzymes in Autolysis of the Embryo Suspensor in Tropaeolum majus L.

Assay of amino-peptidase, acid and alkaline phosphatase, esteraseand ß-glucosidase activity in the haustoria and suspensorof Tropaeolum majus embryos at different stages of developmentis made to evaluate the function of hydrolases in autolysisof the suspensor. Enzyme activities rise to a maximum sometimebetween heart-shaped and cotyledonary phases of embryo development. Tropaeolum majus L. nasturtium, embryology, suspensor, autolysis, hydrolytic enzymes