Ant dipping and meat eating by wild chimpanzees in the kalinzu forest, uganda

New evidence of ant dipping and meat eating by chimpanzees was recorded in the Kalinzu Forest, Uganda. We found stems and branches at the nests of driver ants,Dorylus molestus, just after chimpanzees had left the spot. Fecal samples also revealed that chimpanzees sometimes ate driver ants. The configuration of stems and branches and the condition of holes at the driver ant's nests suggested that chimpanzees used them as wands to dip for ants. The frequency of ant dipping and length of wands may be more related to culturel rather than ecological factors. Although hunting was not seen, we found chim-panzees eating a blue monkey and a redtail monkey. In both cases, they ate meat and leaves alternatively, and shared meat with each other.     

Genetics of neurofibromatosis 1 in Japan: mutation rate and paternal age effect

Summary We have performed formal genetic studies on 26 patients (14 males, 12 females) with neurofibromatosis 1 (von Recklinghausen's disease, NF1) in Japan. Family studies of 74 members of 18 kindreds revealed that 50% of the cases were caused by a new mutation; the mutation rate was assumed to be 7.3–10.5 × 10^-5. A tendency of paternal age effect, which was not accounted for by the maternal age effect, was observed, but live-birth order had no significant effect. Genetic linkage of neurofibromatosis 1 to the NF1 gene or the genetic marker in the pericentric region of chromosome 17 was established in 3 informative families.     

TRIP12 promotes small-molecule-induced degradation through K29/K48-branched ubiquitin chains

1. Download : Download high-res image (184KB)
2. Download : Download full-size image

     

Skeletal Muscle-specific Calpain Is an Intracellular Na+-dependent Protease

Because intracellular [Na⁺] is kept low by Na⁺/K⁺-ATPase, Na⁺ dependence is generally considered a property of extracellular enzymes. However, we found that p94/calpain 3, a skeletal-muscle-specific member of the Ca²⁺-activated intracellular “modulator proteases” that is responsible for a limb-girdle muscular dystrophy (“calpainopathy”), underwent Na⁺-dependent, but not Cs⁺-dependent, autolysis in the absence of Ca²⁺. Furthermore, Na⁺ and Ca²⁺ complementarily activated autolysis of p94 at physiological concentrations. By blocking Na⁺/K⁺-ATPase, we confirmed intracellular autolysis of p94 in cultured cells. This was further confirmed using inactive p94:C129S knock-in (p94CS-KI) mice as negative controls. Mutagenesis studies showed that much of the p94 molecule contributed to its Na⁺/Ca²⁺-dependent autolysis, which is consistent with the scattered location of calpainopathy-associated mutations, and that a conserved Ca²⁺-binding sequence in the protease acted as a Na⁺ sensor. Proteomic analyses using Cs⁺/Mg²⁺ and p94CS-KI mice as negative controls revealed that Na⁺ and Ca²⁺ direct p94 to proteolyze different substrates. We propose three roles for Na⁺ dependence of p94; 1) to increase sensitivity of p94 to changes in physiological [Ca²⁺], 2) to regulate substrate specificity of p94, and 3) to regulate contribution of p94 as a structural component in muscle cells. Finally, this is the first example of an intracellular Na⁺-dependent enzyme.     

DNA Binding and Bending Protein-Based DNA Actuator and its Practical Realization

In the life forms, the biomolecules such as DNA and protein are interacting with each other to maintain their life activity. Simultaneously, these biomolecules form DNA–protein complexes; as a result, the life forms can adjust to the external environment and continue its life activities. Therefore, using these characteristics of the DNA recognition ability of proteins, the novel molecular devices can be established. Here, we show the application of DNA binding and bending protein for design of the DNA actuator and its practical realization. The single polypeptide chain integrated host factor 2 (scIHF2), which is a DNA binding and bending protein, was used to bind to and/or bend the specific domains of DNA. Using this protein and designing the sequences of DNA, mechanical-functionalized DNA-based biomolecular device could be fabricated. Using these mechanisms, DNA binding and bending proteins have great potentials for establishing the DNA actuator for nanobiotechnology and nanotechnology applications.     

Cancer Chemopreventive Activity of Oleanane‐Type Triterpenoids from the Stem Bark of Betula ermanii

In search for cancer chemopreventive agents from natural sources, three oleanane‐ and four known lupane‐type triterpenoids, and sitosterol from the stem bark of Betula ermanii were tested for their inhibitory effects on Epstein–Barr virus early antigen (EBV‐EA) activation induced by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). Among them, 3β‐acetoxy‐12α‐hydroxyoleanan‐13β,28‐olide ( 1 ) and 3β‐acetoxy‐11α,12α‐epoxyoleanan‐13β,28‐olide ( 2 ) were investigated for the inhibitory effect in a two‐stage carcinogenesis test on mouse skin using 7,12‐dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. 3β‐Acetoxy‐11α,12α‐epoxyoleanan‐13β,28‐olide ( 2 ) was found to exhibit the potent antitumor promoting activity in the in vivo carcinogenesis test.     

A Subtype-Specific Critical Period for Neurogenesis in the Postnatal Development of Mouse Olfactory Glomeruli

Sensory input is essential for the normal development of sensory centers in the brain, such as the somatosensory, visual, auditory, and olfactory systems. Visual deprivation during a specific developmental stage, called the critical period, results in severe and irreversible functional impairments in the primary visual cortex. Olfactory deprivation in the early postnatal period also causes significant developmental defects in the olfactory bulb, the primary center for olfaction. Olfactory bulb interneurons are continuously generated from neural stem cells in the ventricular-subventricular zone, suggesting that the olfactory system has plasticity even in adulthood. Here, we investigated the effect of transient neonatal olfactory deprivation on the addition of interneurons to the glomerular layer of the adult mouse olfactory bulb. We found that the addition of one subtype of interneurons was persistently inhibited even after reopening the naris. BrdU pulse-chase experiments revealed that the neonatal olfactory deprivation predominantly affected an early phase in the maturation of this neuronal subtype in the olfactory bulb. Subjecting the mice to odor stimulation for 6 weeks after naris reopening resulted in significant recovery from the histological and functional defects caused by the olfactory deprivation. These results suggest that a subtype-specific critical period exists for olfactory bulb neurogenesis, but that this period is less strict and more plastic compared with the critical periods for other systems. This study provides new insights into the mechanisms of postnatal neurogenesis and a biological basis for the therapeutic effect of olfactory training.     

Determinants of Human CD134 Essential for Entry of Human Herpesvirus 6B

We identified two key amino acid residues within human CD134 (hCD134) that are required for its interaction with human herpesvirus 6B (HHV-6B) and for HHV-6B entry into cells. One of the residues (K79) allows access of the HHV-6B ligand to hCD134. Murine CD134 (mCD134) functioned as an HHV-6B receptor when these two amino acid residues were replaced with homologous human residues. This study identifies both the HHV-6B receptor-ligand interaction and the species-specific determinants of hCD134 essential for HHV-6B entry.