Isolation and characterization of aminopeptidase (Jc-peptidase) from Japanese cedar pollen (Cryptomeria japonica)

An aminopeptidase, Jc-peptidase, was purified from Japanese cedar pollen by seven steps, including precipitation with ammonium sulfate, ion-exchange chromatography, gel filtration, hydrophobic interaction chromatography on phenyl-agarose, and high-performance liquid chromatography. Purified Jc-peptidease has a molecular weight of 42 kDa and hydrolyzes the synthetic substrates of L-phenylalanyl-4-methylcoumaryl-7-amide (Phe-MCA) with Km = 5 x 10(-5) M, Tyr-MCA with Km = 7 x 10(-4) M, Leu-MCA with Km = 1 x 10(-3) M, and Met-MCA with Km = 1 x 10(-3) M. Other MCA analogues such as Arg-MCA or Glu-MCA failed to serve as its substrates. The activity was inhibited in the presence of phebestin, [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valyl]-L-phenylalanine, with Ki = 4.7 x 10(-5) M, or bestatin, [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-L-leucine, with Ki = 1.1 x 10(-4) M. According to amino acid sequence analysis, the N-terminal amino group seems to be blocked. The physiological function of the aminopeptidase (Jc-peptidase) has not been clarified in vivo.     

Improvement of the emulsifying properties of porcine sarcoplasmic proteins with a low-molecular weight surfactant by the two-step emulsification method

The emulsifying properties of porcine sarcoplasmic protein (SP) with or without low-molecular weight surfactants were examined. The emulsifying activity (EA) of SP was weaker than that of sodium caseinate (CA), blood plasma (BP) and whey protein isolates at a protein concentration of 0.5–3%. Sodium chloride decreased the EA of SP. The EA of SP was about one quarter that of CA in the presence of 3% sodium chloride. As homogenization time increased, the EAs of SP and BP decreased. The EA of SP was not influenced by sucrose stearate ester (SE) with a hydrophilic-lipophilic balance (HLB) value of 16 (SE-16) but was decreased by those with HLB values of 5 and 1. Low-molecular weight surfactants such as SE-16, Tween 80 and sodium cholate improved the EA of SP with the two-step emulsification method: corn oil was previously emulsified with the surfactant before addition of SP and homogenization. In the case of the addition of SE-16 as primary emulsifier, the EA was about twice as high as that of SP alone. The same effect was shown in the emulsions formed by CA and soy protein isolate. These results indicate that the emulsifying properties of meat protein would be improved by the addition of a low-molecular weight surfactant in a two-step emulsification.     

Polymorphisms in the canine glutamate transporter-1 gene: identification and variation among five dog breeds

Excitatory amino acid transporters (EAATs) are important for terminating glutamatergic neurotransmission and protect central nervous system (CNS) neurons from glutamatergic excitotoxicity. We selected these genes as targets that may relate to canine behavioral traits. After screening four EAAT genes (glutamate transporter-1; GLT-1, excitatory amino acid transporter 4; EAAT4, excitatory amino acid carrier; EAAC1, glutamate/aspartate transporter; GLAST) for single nucleotide polymorphisms (SNPs), we identified two silent SNPs (C129T and T471C) in the GLT-1 gene. We genotyped 193 dogs of 5 breeds and found significant variation among breeds in these two SNPs in GLT-1. The C129T polymorphism was not observed in Malteses and Miniature Schnauzers. These results suggest that polymorphisms in the GLT-1 gene may be useful markers for examining how the genetic background relates to the behavioral traits of dogs.     

The time course of lymph drainage from the peritoneal cavity in beagle dogs

Lymph drainage routes from the abdominal and pelvic cavities in beagle dogs were observed serially by following the time course of India ink administered intraperitoneally. Four systems of lymph drainage routes from the peritoneal cavity were observed in this study. The earliest drainage returned to the cranial mediastinal lymph nodes via the sternal lymph vessels; subsequently, the sternal lymph nodes located along the internal thoracic artery became involved. Then, a drainage route via the lymph vessel along the left vagus nerve was observed. The final drainage route flowed into the lateral lymph vessel through the thoracic duct located on the vertebra. These results show that India ink is absorbed from the peritoneal cavity, and that the lymph drainage first flows mainly towards the cranial mediastinal lymph nodes through the ventral lymphatic channels. Our serial observations suggest that, over time, the lymph drainage routes changed from the ventral abdominal to the dorsal thoracic lymphatic channels in the thorax.     

A comparison of the behavioral profiles of purebred dogs in Japan to profiles of those in the United States and the United Kingdom

To clarify the behavioral profiles of 56 pure breeds of dogs in Japan, 96 small-animal veterinarians participated in a questionnaire survey using the same criteria as in preceding studies conducted in the United States and the United Kingdom. We found significant differences among breeds in all behavioral traits examined. In addition, gender differences were revealed in terms of aggression to dogs, territorial defense, excitability, general activity, dominance over owner, destructiveness, watchdog barking, and snapping at children, which were all rated higher in males than females, whereas obedience training and housebreaking ease were rated higher in females. No gender differences were evident in playfulness, excessive barking, or affection demand. Using factor analyses, "aggressiveness", "reactivity", and "trainability" were determined to be consistent with results found in the US and UK surveys. On the basis of these factor scores, seven groups of breeds were determined by cluster analysis to compare to the US survey; 22 of the 38 breeds common with the US survey were categorized into the same groups as those in that survey. The results demonstrated differences in canine behavioral predisposition among breeds and between genders. The similarity in the results between our study and previous surveys, which involved distinct geographical locales, suggests that the genetic basis of breed-specific temperamental traits is manifested irrespective of the cultural or regional identities of the owners.     

The muscle protein Dok-7 is essential for neuromuscular synaptogenesis

The formation of the neuromuscular synapse requires muscle-specific receptor kinase (MuSK) to orchestrate postsynaptic differentiation, including the clustering of receptors for the neurotransmitter acetylcholine. Upon innervation, neural agrin activates MuSK to establish the postsynaptic apparatus, although agrin-independent formation of neuromuscular synapses can also occur experimentally in the absence of neurotransmission. Dok-7, a MuSK-interacting cytoplasmic protein, is essential for MuSK activation in cultured myotubes; in particular, the Dok-7 phosphotyrosine-binding domain and its target in MuSK are indispensable. Mice lacking Dok-7 formed neither acetylcholine receptor clusters nor neuromuscular synapses. Thus, Dok-7 is essential for neuromuscular synaptogenesis through its interaction with MuSK.     

Dystroglycan function requires xylosyl- and glucuronyltransferase activities of LARGE

Posttranslational modification of alpha-dystroglycan (α-DG) by the like-acetylglucosaminyltransferase (LARGE) is required for it to function as an extracellular matrix (ECM) receptor. Mutations in the LARGE gene have been identified in congenital muscular dystrophy patients with brain abnormalities. However, the precise function of LARGE remains unclear. Here we found that LARGE could act as a bifunctional glycosyltransferase, with both xylosyltransferase and glucuronyltransferase activities, which produced repeating units of [-3-xylose-α1,3-glucuronic acid-β1-]. This modification allowed α-DG to bind laminin-G domain-containing ECM ligands.     

Traits of shattering resistant buckwheat ‘W/SK86GF’

Seed shattering is a significant problem with buckwheat, especially at harvesting time. Several reports have shown that a green-flower mutant of buckwheat, such as W/SK86GF, has a strong pedicel. Although a strong pedicel may provide some resistance to shattering in the field, no study has thoroughly examined this issue. In this paper, we demonstrate that a W/SK86GF has shattering resistance by comparing the degrees of shattering of W/SK86GF and Kitawasesoba (leading variety of Hokkaido with non-green-flower traits) through a test for four years, including a typhoon hit year in the field. In a non-typhoon year, the shattering seed ratio (shattering seed weight/(yield + shattering seed weight) × 100) of W/SK86GF at maturing time +15 days (+15D) was lower than that of Kitawasesoba. In a typhoon hit year, the shattering seed ratios of Kitawasesoba at maturing time and +15D were surprisingly high, 14.4 and 21.1%, respectively. On the other hand, those of W/SK86GF were only 3.08% and 2.57%, respectively; indicating W/SK86GF is promising as a shattering resistant line even in a typhoon hit year. From these results, shattering resistance of W/SK86GF can be evaluated after maturing time such as +15D and pedicel strength would confer W/SK86GF a shattering resistant trait.     

应用iTRAQ结合2D LC-MS/MS技术分析草菇同核和异核菌丝蛋白质组

首次利用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantification,iTRAQ)技术结合二维液相色谱串联质谱对草菇(Volvariella volvacea)同核和异核菌丝蛋白质组进行研究。采用QExactive质谱鉴定并经MASCOT软件搜库,对所有鉴定蛋白进行主成分分析(principal component analysis,PCA)、层次聚类(hierarchical clustering)分析和GO(gene ontology)注释,并进行生物信息学分析。结果共获得2335个不同肽段,鉴定到1039个蛋白,其中1030个蛋白具有定量信息。在同核菌丝中显著上调蛋白83个,下调蛋白97个,表明iTRAQ标记技术结合二维液相色谱串联质谱可有效地分离和鉴定草菇菌丝蛋白质组。该研究结果为更深入全面地研究草菇菌丝蛋白质组学奠定基础。     

Age Difference in Morphology and Immunohistology inthe Thymus and Spleen in Crl:CD (SD) Rats

We investigated chronological changes in immunohistochemical phenotyping in the thymus and spleen in Crl:CD rats up to the age of about one year. In the thymus, T cells increased markedly from 3 to 4 weeks of age. Proliferating cells also increased markedly at these points. B cells tended towards an increase with age. In the spleen, white pulp increased until 9 weeks of age and remained fairly stable thereafter. In the periarteriolar lymphoid sheath and marginal zone, T cells gradually increased until 9 weeks of age and became almost flat thereafter. In the lymph follicle, T cells increased with age. B cells tended towards an increase with age in all areas of the spleen. It was concluded that development of the thymus was most marked from 3 to 4 weeks of age and that both the thymus and spleen had matured by 9 weeks of age.