A population genetic study on the transition from Jomon people to Yayoi people

In the study on the origin of Japanese, one of main unsolved problems is the transition from the Jomon people to the Yayoi people. The main difficulty in solving this problem has been the lack of suitable skeletal materials belonging to the time between the two periods, i.e. the final Jomon and the early Yayoi Periods. Therefore, we know few details of the transition period. It is important to know who carried out a drastic change of the Yayoi culture during this transitional period, i.e. the native Jomon people or the immigrant people. By introducing population genetic models, we show that a view that the immigrant people had a significant genetic contribution to the origin of Japanese is compatible with results from anthropological and archeological studies. This result implies that the immigrant people were mainly responsible for the drastic cultural change during the transitional period.     

Alpneumines A–H,new anti-melanogenic indole alkaloids from Alstonia pneumatophora

Eight new indole alkaloids, alpneumines A–H (1–8) were isolated from the Malaysian Alstonia pneumatophora (Apocynaceae) and their structures were determined by MS and 2D NMR spectroscopic methods. Alpneumines E and G (5 and 7), vincamine, and apovincamine showed anti-melanogenesis in B16 mouse melanoma cells.     

Prediction of the coding sequences of mouse homologues of FLJ genes: the complete nucleotide sequences of 110 mouse FLJ-homologous cDnas identified by screening of terminal sequences of cDNA clones randomly sampled from size-fractionated libraries.

We have been conducting a mouse cDNA project to predict protein-coding sequences of mouse KIAA-homologous genes since 2001. As an extension of this project, we also started to accumulate mouse cDNA clones homologous to the human FLJ cDNA clones which are another long cDNA resource produced in our institute. We have isolated the cDNA clones from size-fractionated cDNA libraries derived from five different mouse tissues and natural killer T-cells. Although the human FLJ cDNA clones were originally derived from human spleen libraries, one-third of their mouse homologues were obtained from the brain library. We designated these homologues "mFLJ" plus a 5-digit number and herein characterized 110 mFLJ cDNA clones. We assigned an integrity of the CDSs from the comparison of the 110 cDNA clones with the corresponding human FLJ cDNA clones. The average size of the 110 mouse cDNA sequences was 3.8 kb and that of the deduced amino acid sequences from their longest CDS in each cDNA was 663 amino acid residues. Homology and/or motif search against public databases revealed new domains and/or motifs in 26 mFLJ gene products which provide additional speculation regarding the function of FLJ genes.     

DOES ELASTIN CONTRIBUTE TO THE PERSISTENCE OF CORPORA ALBICANTIA IN THE OVARY OF THE COMMON DOLPHIN (DELPHINUS DELPHIS)

The corpora albicantia (CAs) from the ovaries of 39 common dolphins ( Delphinus delphis ) caught in driving fisheries were used, and histologically and immunohistochemically examined. The area of each corpus albicans (CA) and the proportion of that area occupied by elastin were measured using NIH-image software. In all CAs, elastoid material (EM) was apparent although EM area varied in each CA. CAs increased in number with dolphin age. Smaller CAs contained a higher proportion of EM. EM was completely digested by elastase, but not by collagenase. Furthermore, EM was immunostained with anti-α-elastin antibody. These results demonstrated that EM was elastin. The present study is the first to describe the presence of elastin in cetacean CAs. The higher proportion of elastin in small-sized CAs of common dolphins is suggested as the likely cause of the persistence of CA.     

Factors influencing eating ability of old in-patients in a rehabilitation hospital in Japan

Objectives: This study was designed to determine the factors influencing eating ability of old in‐patients in a rehabilitation hospital. Design: Cross‐sectional investigation. Setting: Forty‐six in‐patients in the rehabilitation ward of Hashimoto Hospital in Kagawa Prefecture in Japan were investigated using a multi‐disciplinary approach. Main outcome measures: Age, gender, state of dentition, muscle activity of lip, cheek and tongue, biting force, salivary flow rate per a minute (SFR), masticatory ability for gummy jelly, swallowing ability, texture of meal, independency of walking (Functional Independence Measure=FIM) and ability to communicate. Results: Bivariate analysis for the relationship between surveyed items and masticatory ability (chi‐square test) identified that better masticatory ability for gummy jelly was associated with age (<85 years), gender (male), state of dentition (dentate), SFR (high), activity of lip (good), biting force (high), swallowing ability (good) and activity of communication (high). Among these items, SFR (p=0.001), gender (p=0.004), ability to communicate (p=0.005) and age (p=0.012) were found having an influence on the masticatory ability (logistic regression analysis). On the other hand, age (<85years), gender (male), SFR (high), activity of lip (good), activity of cheek (good), biting force (high), masticatory ability (good) and swallowing ability (good) had a relationship with normal texture of meal. In regression analysis, only two items, activity of lip (p=0.003) and swallowing ability (p=0.024) emerged as factors on texture of meal. Conclusions: Masticatory ability for gummy jelly was influenced by cognitive function and was excluded from the factors on the state of meal. These results suggested the limitation of evaluation using test food, so dentists should observe eating behaviour of in‐patients. In addition, dentists should pay attention to the activity of the lip and swallowing ability as well as dentition and prostheses in the rehabilitation of eating ability. As SFR was the most significant factor on masticatory ability, this emphasizes the necessity of care for dry mouth caused by side effects of multi‐medication     

Crystal structure of chloroplastic ascorbate peroxidase from tobacco plants and structural insights into its instability

Ascorbate peroxidase (APX) is a heme-containing protein that plays a central role in scavenging H(2)O(2) in higher plants. The structure of stromal APX (sAPX) was determined at 1.6 A to an R-factor of 19.1% and an R-free-factor of 22.3%. The electrostatic potential of the gamma-channel that connects the molecular surface of sAPX to the gamma-edge of heme was more positive than that of cytosolic APX (cAPX) from pea, so sAPX might bind more easily with ascorbate than cAPX. The overall structure of sAPX was similar to those of cAPX from pea and cytochrome c peroxidase (CCP) from yeast, with a substantial difference in a loop structure located in the vicinity of the heme. The side chain of Arg169 in sAPX corresponding to His169 in cAPX and His181 in CCP extended in the opposite direction from the heme, forming two hydrogen bonds with carbonyl groups in the loop structure. The rapid inactivation of sAPX might be due to the characteristic conformation of Arg169 owing to the loop structure of sAPX.     

Phosphorylation of Fanconi anemia protein, FANCA, is regulated by Akt kinase

Phosphorylation of the Fanconi anemia complementation group A (FANCA) protein is thought to be important for the function of the FA pathway. However, the kinase for FANCA (so-called FANCA-PK) remains to be identified. FANCA has a consensus sequence for Akt kinase near serine 1149 (Ser1149), suggesting that Akt can phosphorylate FANCA. We performed in vitro kinase assays using as substrate either a GST-fusion wild-type (WT) FANCA fragment or a GST-fusion FANCA fragment containing a mutation from serine to alanine at 1149 (FANCA-S1149A). These experiments confirmed that FANCA is phosphorylated at Ser 1149, in vitro. However, (32)P-orthophosphate labeling experiments revealed that FANCA-S1149A was more efficiently phosphorylated than WT-FANCA. Furthermore, phosphorylation of wild-type FANCA was blocked by coexpression of a constitutively active (CA)-Akt and enhanced by a dominant-negative (DN) Akt. Our results suggest that Akt is a negative regulator of FANCA phosphorylation.     

Interaction of plexin-B1 with PDZ domain-containing Rho guanine nucleotide exchange factors

The Rho family GTPase has been implicated in plexin-B1, a receptor for Semaphorin 4D (Sema4D), mediating signal transduction. Rho may also play a function in this signaling pathway as well as Rac, but the mechanisms for Rho regulation are poorly understood. In this study, we have identified two kinds of PDZ domain-containing Rho-specific guanine nucleotide exchange factors (RhoGEFs) as proteins interacting with plexin-B1 cytoplasmic domain. These PDZ domain-containing RhoGEFs showed significant homology to human KIAA0380 (PDZ-RhoGEF) and LARG (KIAA0382), respectively. Both KIAA0380 and LARG could bind plexin-B1 and a deletion mutant analysis of plexin-B1, KIAA0380 and LARG revealed that KIAA0380 and LARG bound plexin-B1 cytoplasmic tail through their PDZ domains. The tissue distribution analysis indicated that plexin-B1 was co-localized with KIAA0380 and LARG in various tissues. Immunocytochemical analysis showed that LARG was recruited to plasma membrane by plexin-B1. These results suggest that PDZ domain-containing RhoGEFs play a role in Sema4D-plexin-B1 mediating signal transduction.