Carbohydrates and carbohydrate esters of ferulic acid released from cell walls of Lolium multiflorum by treatment with cellulolytic enzymes

41% of the cell walls from mature leaf blades of Lolium multiflorum were digested by treatment during 14 days with C₁ enzyme (cellulase) which had been purified by gel filtration and ion-exchange chromatography. Cellobiose was the main sugar released from the walls, together with some glucose and higher oligosaccharides. Considerable amounts of carbohydrate esters of ferulic and p-coumaric acids were also released. When the C₁ enzyme was further purified by isoelectric focusing, only 8% of the cell walls were digested. Purified C_x (CM-cellulase) containing β-glucosidase digested 51% of the cell walls in 16 hours: the major component detected in the soluble products was glucose together with some β (1 → 4)-xylobiose, xylose and arabinose. Higher oligosaccharides and carbohydrate esters of ferulic and p-coumaric acids were also present. It was shown that these acids were present in the cell walls mainly in the trans-configuration.     

Genetic ablation of the CDP/Cux protein C terminus results in hair cycle defects and reduced male fertility

Murine CDP/Cux, a homologue of the Drosophila Cut homeoprotein, modulates the promoter activity of cell cycle-related and cell-type-specific genes. CDP/Cux interacts with histone gene promoters as the DNA binding subunit of a large nuclear complex (HiNF-D). CDP/Cux is a ubiquitous protein containing four conserved DNA binding domains: three Cut repeats and a homeodomain. In this study, we analyzed genetically targeted mice (Cutl1(tm2Ejn), referred to as Delta C) that express a mutant CDP/Cux protein with a deletion of the C terminus, including the homeodomain. In comparison to the wild-type protein, indirect immunofluorescence showed that the mutant protein exhibited significantly reduced nuclear localization. Consistent with these data, DNA binding activity of HiNF-D was lost in nuclear extracts derived from mouse embryonic fibroblasts (MEFs) or adult tissues of homozygous mutant (Delta C(-/-)) mice, indicating the functional loss of CDP/Cux protein in the nucleus. No significant difference in growth characteristics or total histone H4 mRNA levels was observed between wild-type and Delta C(-/-) MEFs in culture. However, specific histone genes (H4.1 and H1) containing CDP/Cux binding sites have reduced expression levels in homozygous mutant MEFs. Stringent control of growth and differentiation appears to be compromised in vivo. Homozygous mutant mice have stunted growth (20 to 50% weight reduction), a high postnatal death rate of 60 to 70%, sparse abnormal coat hair, and severely reduced fertility. The deregulated hair cycle and severely diminished fertility in Cutl1(tm2Ejn/tm2Ejn) mice suggest that CDP/Cux is required for the developmental control of dermal and reproductive functions.     

No evidence for prolonged excretion of polioviruses in persons with residual paralytic poliomyelitis in Ethiopia, Pakistan and Guatemala.

Persons who have developed acute flaccid paralysis following infection with wild-type polioviruses or vaccine-associated paralytic poliomyelitis usually excrete polioviruses for only a few weeks. However, some patients with paralytic poliomyelitis have had prolonged excretion of polioviruses for periods of up to 10 years after onset of disease. Most prolonged excretors have been identified in industrialized countries. We studied 348 patients 2-28 years old in Ethiopia, Pakistan and Guatemala with residual paralytic poliomyelitis to determine if they had IgA or IgG deficiency or persistent poliomyelitis excretion at least 1 year after onset of disease. None of the 348 affected individuals had IgG deficiency or persistent poliovirus excretion. One child had borderline low serum IgA concentration. Since we did not study children under 2 years of age, persons born with IgG deficiency disorders may have died in developing countries where replacement immunoglobulin therapy is not readily available. Nevertheless, persistent poliovirus excretion among persons 2 years of age and older with residual paralytic poliomyelitis is uncommon in developing countries.     

Responses of legume versus nonlegume tropical tree seedlings to elevated CO2 concentration

We investigated responses of growth, leaf gas exchange, carbon-isotope discrimination, and whole-plant water-use efficiency (W(P)) to elevated CO(2) concentration ([CO(2)]) in seedlings of five leguminous and five nonleguminous tropical tree species. Plants were grown at CO(2) partial pressures of 40 and 70 Pa. As a group, legumes did not differ from nonlegumes in growth response to elevated [CO(2)]. The mean ratio of final plant dry mass at elevated to ambient [CO(2)] (M(E)/M(A)) was 1.32 and 1.24 for legumes and nonlegumes, respectively. However, there was large variation in M(E)/M(A) among legume species (0.92-2.35), whereas nonlegumes varied much less (1.21-1.29). Variation among legume species in M(E)/M(A) was closely correlated with their capacity for nodule formation, as expressed by nodule mass ratio, the dry mass of nodules for a given plant dry mass. W(P) increased markedly in response to elevated [CO(2)] in all species. The ratio of intercellular to ambient CO(2) partial pressures during photosynthesis remained approximately constant at ambient and elevated [CO(2)], as did carbon isotope discrimination, suggesting that W(P) should increase proportionally for a given increase in atmospheric [CO(2)]. These results suggest that tree legumes with a strong capacity for nodule formation could have a competitive advantage in tropical forests as atmospheric [CO(2)] rises and that the water-use efficiency of tropical tree species will increase under elevated [CO(2)].     

Neighbouring chimpanzee communities show different preferences in social grooming behaviour

Grooming handclasp (GHC) behaviour was originally advocated as the first evidence of social culture in chimpanzees owing to the finding that some populations engaged in the behaviour and others do not. To date, however, the validity of this claim and the extent to which this social behaviour varies between groups is unclear. Here, we measured (i) variation, (ii) durability and (iii) expansion of the GHC behaviour in four chimpanzee communities that do not systematically differ in their genetic backgrounds and live in similar ecological environments. Ninety chimpanzees were studied for a total of 1029 h; 1394 GHC bouts were observed between 2010 and 2012. Critically, GHC style (defined by points of bodily contact) could be systematically linked to the chimpanzee''s group identity, showed temporal consistency both within and between groups, and could not be accounted for by the arm-length differential between partners. GHC has been part of the behavioural repertoire of the chimpanzees under study for more than 9 years (surpassing durability criterion) and spread across generations (surpassing expansion criterion). These results strongly indicate that chimpanzees'' social behaviour is not only motivated by innate predispositions and individual inclinations, but may also be partly cultural in nature.     

Genetic Diversity and Histo-Blood Group Antigen Interactions of Rhesus Enteric Caliciviruses

Recently, we reported the discovery and characterization of Tulane virus (TV), a novel rhesus calicivirus (CV) (T. Farkas, K. Sestak, C. Wei, and X. Jiang, J. Virol. 82:5408-5416, 2008). TV grows well in tissue culture, and it represents a new genus within Caliciviridae, with the proposed name of Recovirus. We also reported a high prevalence of CV antibodies in macaques of the Tulane National Primate Research Center (TNPRC) colony, including anti-norovirus (NoV), anti-sapovirus (SaV), and anti-TV (T. Farkas, J. Dufour, X. Jiang, and K. Sestak, J. Gen. Virol. 91:734-738, 2010). To broaden our knowledge about CV infections in captive nonhuman primates (NHP), 500 rhesus macaque stool samples collected from breeding colony TNPRC macaques were tested for CVs. Fifty-seven (11%) samples contained recovirus isolates. In addition, one NoV was detected. Phylogenetic analysis classified the recovirus isolates into two genogroups and at least four genetic types. The rhesus NoV isolate was closely related to GII human NoVs. TV-neutralizing antibodies were detected in 88% of serum samples obtained from primate caretakers. Binding and plaque reduction assays revealed the involvement of type A and B histo-blood group antigens (HBGA) in TV infection. Taken together, these findings indicate the zoonotic potential of primate CVs. The discovery of a genetically diverse and prevalent group of primate CVs and remarkable similarities between rhesus enteric CVs and human NoVs opens new possibilities for research involving in vitro and in vivo models of human NoV gastroenteritis.Caliciviruses (CV) are important human and animal pathogens, causing a wide variety of diseases in their respective hosts. The family Caliciviridae consists of five established genera (Norovirus, Sapovirus, Lagovirus, Vesivirus, and Nebovirus). Recently, two new calicivirus genera have been proposed, represented by the Tulane virus (Recovirus) and the St. Valerien-like viruses (Valovirus) (11-13, 24, 36, 37, 39).NoVs are recognized as the leading cause of epidemics of gastroenteritis (GE), causing 80 to 90% of nonbacterial GE outbreaks and more than 50% of all food-related GE outbreaks (7, 8, 29). They are also an important cause of sporadic GE in both children and adults. Based on phylogenetic analysis, NoVs are divided into five genogroups and more than 30 genetic clusters or genotypes (9, 46). This high genetic and, likely, antigenic variation, combined with the lack of a tissue culture or animal model, represent major obstacles for NoV research.NoVs with close genetic and antigenic relatedness to human NoVs have been isolated from various animal species (6, 28, 33, 41). This not only provided opportunities for using some of these viruses as surrogates for human NoV research (44) but also raised the concern of the possible zoonotic nature of CV gastroenteritis.Based on results of in vitro binding assays, volunteer challenge studies, and the analysis of NoV outbreaks, it was proposed that histo-blood group antigens (HBGA), including the ABO, Lewis, and secretor-type HBGAs, function as the NoV receptors (17, 19, 20, 27, 32). The involvement of other host factors in NoV replication and susceptibility to infection also has been implicated (14, 43).Previously, we reported the isolation and characterization of a novel CV (Tulane virus; TV) from stool samples of juvenile rhesus macaques (11). TV represents a newly proposed genus (Recovirus) within Caliciviridae that phylogenetically shares a common origin with NoVs; however, TV can be grown in tissue culture (11). We also reported a high prevalence of anti-NoV, anti-SaV binding, and anti-TV-neutralizing (VN) antibodies in colony macaques, suggesting that CV infections are frequent in captive nonhuman primates (NHP) (10). The few NoV challenge studies conducted also suggest that NHPs are susceptible to NoV infection. Chimpanzees inoculated with the Norwalk virus developed seroresponses and virus shedding but without the manifestation of clinical disease (45). Subekti et al. reported the development of clinical illness characterized by diarrhea, dehydration, vomiting, and virus shedding in newborn pigtail macaques inoculated with the Toronto virus (40). In a study conducted by Rockx et al., one of the three rhesus macaques infected with Norwalk virus developed virus-specific IgM and IgG responses and shed the virus for 19 days postinoculation (38). To date, however, direct evidence of natural NoV or SaV infection in NHPs is missing. Moreover, the prevalence and genetic diversity of recoviruses have yet to be studied.In this study, we undertook the molecular detection and genetic analysis of CVs circulating in colony macaques and examined the role of HBGAs in recovirus infection.     

Albumin peptide: a molecular marker for trauma/hemorrhagic-shock in rat mesenteric lymph

Vascular permeability and endothelial cell damage has been shown to occur in rats subjected to trauma with hemorrhagic-shock. Although the factors responsible for the endothelial cell injury are unknown, it has been hypothesized that toxic factors produced in response to hemorrhagic-shock originate in the gut and are absorbed into the mesenteric lymphatics. Consistent with this hypothesis, it has been shown that lymph collected from animals subjected to trauma with hemorrhagic-shock (T/HS) results in a marked decrease in endothelial cell viability both in vitro and in vivo. We therefore compared the lymph collected pre-T/HS to samples collected during, and up to 3 h post-T/HS in order to identify a factor present or increased in post-T/HS lymph. This analysis revealed that a single cationic peptide band was significantly increased in post-T/HS lymph, but not in lymph from control animals subjected to trauma without hemorrhagic-shock (T/SS). This peptide was subsequently identified as the N-terminal 24 amino acids of rat serum albumin (RSA) by mass spectrometry and amino acid sequencing. Although the measured increase in the albumin peptide correlates with detectable shock lymph-induced endothelial cell toxicity, the peptide was not toxic to endothelial cells. We therefore propose that the significant increase in the albumin peptide is a marker for post-T/HS lymph-induced endothelial cell toxicity.     

Comparative genomics enabled the isolation of the R3a late blight resistance gene in potato

Comparative genomics provides a tool to utilize the exponentially increasing sequence information from model plants to clone agronomically important genes from less studied crop species. Plant disease resistance (R) loci frequently lack synteny between related species of cereals and crucifers but appear to be positionally well conserved in the Solanaceae. In this report, we adopted a local RGA approach using genomic information from the model Solanaceous plant tomato to isolate R3a, a potato gene that confers race-specific resistance to the late blight pathogen Phytophthora infestans. R3a is a member of the R3 complex locus on chromosome 11. Comparative analyses of the R3 complex locus with the corresponding I2 complex locus in tomato suggest that this is an ancient locus involved in plant innate immunity against oomycete and fungal pathogens. However, the R3 complex locus has evolved after divergence from tomato and the locus has experienced a significant expansion in potato without disruption of the flanking colinearity. This expansion has resulted in an increase in the number of R genes and in functional diversification, which has probably been driven by the co-evolutionary history between P. infestans and its host potato. Constitutive expression was observed for the R3a gene, as well as some of its paralogues whose functions remain unknown.     

A Bmp Reporter with Ultrasensitive Characteristics Reveals That High Bmp Signaling Is Not Required for Cortical Hem Fate

Insights into Bone morphogenetic protein (Bmp) functions during forebrain development have been limited by a lack of Bmp signaling readouts. Here we used a novel Bmp signaling reporter (“BRE-gal” mice) to study Bmp signaling in the dorsal telencephalon. At early stages, BRE-gal expression was restricted to the dorsal telencephalic midline. At later stages, strong BRE-gal expression occurred in neurons of the marginal zone and dentate gyrus. Comparisons to nuclear phospho-Smad1/5/8 (pSmad) and Msx1 indicated that BRE-gal expression occurred exclusively in neural cells with high-level Bmp signaling. BRE-gal responsiveness to Bmps was confirmed in reporter-negative cortical cells cultured with Bmp4, and both in vivo and in vitro, BRE-gal expression was switch-like, or ultrasensitive. In the early dorsal telencephalon, BRE-gal expression negatively correlated with the cortical selector gene Lhx2, indicating a BRE-gal expression border that coincides with the cortex-hem boundary. However, in Lhx2 null chimeras, neither BRE-gal nor nuclear pSmad increases were observed in ectopic hem cells. These findings establish BRE-gal as an ultrasensitive reporter of Bmp signaling in the dorsal telencephalon, imply that hem fate can be specified at different Bmp signaling intensities, and suggest that Lhx2 primarily regulates the responses to – rather than the intensity of – Bmp signaling in dorsal telencephalic cells.     

Microscopical study of experimental wound healing in <Emphasis Type="Italic">Notothenia coriiceps</Emphasis> (Cabeçuda) at 0°C

Notothenia coriiceps (Cabeçuda) is an Antarctic benthic fish frequently found with lesions in the tegument caused by seal predation. We have investigated epidermal repair in these animals by means of a microscopic study of experimental wound healing at 0°C. At 24–48 h after wound induction, mucous exudate and necrotic lining cells covered the wound. At 7–14 days, an epidermal tongue could be discerned, folded at the tip, with intercellular oedema between the tip and the wound border. After 23–30 days, the wound was completely closed and the migrating epidermis, with intercellular oedema, was reduced. By 45–90 days, melanocytes progressively increased in the epidermis but no scales were formed. The inflammatory infiltrate was mainly composed of neutrophils after 7 days, at which time they were mostly replaced by macrophages; lymphocytes and plasma cells were also present. The border epidermis slid towards the centre, folding at the tip and finally fusing to form a diaphragm. The cells of the epidermis began to multiply only after complete closure of the wound. The lack of scale formation on induced and naturally found wounds, even after 90 days, suggests that different mechanisms in wound repair occur at 0°C from those in fish from temperate and tropical environment. This is the first report of successful wound repair at polar temperatures, indicating the adaptation of N. coriiceps to the Antarctic environment.The financial support from CNPq (68.0047/00-0 and 48.0262/00-4 grants), PROANTAR, SECIRM and FAPESP is greatly appreciated. Professor E.L. Cooper is partially supported by funds from the Hewlett Foundation to the Latin American Center, UCLA.