The C57BL/6J-fe/fe mouse is a coat color mutant. The coat color of the homozygote mouse becomes progressively lighter with advancing age. The faded gene (fe) of C57BL/6J-fe/fe was mapped in a 2.0 cM distal to D10mit191 by our group. To make a high-resolution map, we used the Korean wild mouse (KWHM) for a backcross panel, which was captured in 1995 and has been maintained as an inbred line by our laboratory. In the inter-specific backcross panel (N=400), the fe gene was mapped to 1.0 cM distal to D10mit156. The gene order was defined: centromere -D10mit3/85 (1.3+/-0.6 cM)-D10mit155 (1.3+/-0.6 cM)-D10mit191 (2.0+/-0.7 cM)-D10mit156 (1.0+/-0.5 cM)-fe-D10mit193 (1.3+/-0.6 cM)-D10mit54 (1.0+/-0.5 cM)-D10mit44 (8.5+/-1.4 cM)-D10mit42 (10.0+/-1.5 cM). The measured distance between D10mit191 and D10mit 44 differed in both inter-specific (DBA/2) and intra-specific (KWHM) backcross panels (14.2 vs 13.8 cM). Taken together, our high-resolution linkage map of the fe locus from an intra-specific backcross panel will provide a good entry point to isolate the fe gene.
Animals ; Centromere ; Chromosomes, Human, Pair 10 ; Gene Order ; Hair Color ; Homozygote ; Mice

Circling mouse (C57BL/6J-cir/cir) deleted the transmembrane inner ear (Tmie) gene is an animal model for human non-syndromic recessive deafness, DFNB6. In circling mouse, hair cells in the cochlea have degenerated and hair bundles have become irregularity as time goes on. Tmie protein carries out a function of the mechanoelectrical transduction channel in cochlear hair cells. Myosin7a (MYO7A) protein has key roles in development of the cochlear hair bundles as well as in the function of cochlear hair cells. To find whether Tmie protein interacts with MYO7A proteins in the cochlea postnatal developmental stage, we investigated expression of the MYO7A proteins in the cochlear hair cells of circling mice by western blot analysis and whole mount immunofluorescence at postnatal day 5 (P5). The expression of MYO7A showed statistically significant increase in the cochlea of C57BL/6J-+/cir and C57BL/6J-cir/cir mice than that of C57BL/6J-+/+ mice. The MYO7A intensity of the cochlear hair cells also increased in C57BL/6J-+/cir and C57BL/6J-cir/cir mice compared with those of C57BL/6J-+/+ mice. Taken together, the results indicate that Tmie protein may have an important role with MYO7A protein in the development and maintenance of the stereociliary bundles during postnatal developmental stage of the cochlea.
Animals ; Blotting, Western ; Cochlea ; Deafness ; Ear, Inner ; Fluorescent Antibody Technique ; Hair ; Hair Cells, Auditory* ; Humans ; Mice* ; Models, Animal

The C57BLKS/J-Lepr(db) mouse has a point mutation in the leptin receptor gene and is one of the most useful animal model for non-insulin dependent diabetes mellitus in human. Since the homozygote of C57BLKS/J-Lepr(db) mouse is infertile, detection of point mutation in the leptin receptor gene is important for efficient maintaining strains as well as mass production of homozygotes. To develop a rapid and efficient genotyping method for C57BLKS/J-Lepr(db) mouse, the tetra-primer amplification-refractory mutation system polymerase chain reaction (ARMS-PCR) was used. The 407 and 199 bp PCR products were amplified from normal (+/+) mice; while the 407 and 268 bp PCR products were amplified from homozygotes (db/db) mice; and the 407, 268, and 199 bp PCR products were amplified from heterozygotes (db/+) mice. This result showed that the tetra-primer ARMS-PCR analysis by us is suitable to detect point mutation of the leptin receptor gene. Taken together, our method will dramatically reduce animal use for maintenance of strains as well as production of homozygote in the C57BLKS/J-Lepr(db) strains.
Animals ; Diabetes Mellitus ; Heterozygote ; Homozygote ; Humans ; Leptin* ; Mice* ; Models, Animal ; Point Mutation ; Polymerase Chain Reaction ; Receptors, Leptin*

The published article includes an error in Figure 1.

Laboratory inbred mice are used widely and commonly in biomedical research, but inbred mice do not have a big enough gene pool for the research. In this study, genetic and morphometric analyses were performed to obtain data on the characteristics of a newly developing inbred strain (KWM/Hym) captured from Chuncheon, Korea. All of five Korean wild male mice have the zinc-finger Y (ZfY) gene. Also, all of 19 Korean wild mice used in this analysis have the AKV-type murine leukemia virus gene, indicating that Korean wild mice might be Mus musculus musculus. To identify the genetic polymorphism in KWM/Hym, SNP analysis was performed. In a comparison with 28 SNP markers, there was a considerable difference between KWM/Hym and several inbred strains. The homogeneity between KWM/Hym and the inbred strains was as follows: C57BL/6J (39.3%), BALB/c AJic (42.9%), and DBA/2J (50%). KWM/Hym is most similar to the PWK/PhJ inbred strain (96.4%) derived from wild mice (Czech Republic). To identify the morphometric characteristics of KWM/Hym, the external morphology was measured. The tail ratio of male and female was 79.60±3.09 and 73.55±6.14%, respectively. KWM/Hym has short and agouti-colored hairs and its belly is white with golden hair. Taking these results together, KWM/Hym, a newly developing inbred mouse originated from wild mouse, might be use as new genetic resources to overcome the limitations of the current laboratory mice.
Animals ; Female ; Gangwon-do* ; Gene Pool ; Hair ; Humans ; Korea* ; Leukemia Virus, Murine ; Male ; Mice* ; Polymorphism, Genetic ; Tail

Components of silk including silk fibroin have long been used as anti-diabetic remedies in oriental medicine. However, detailed mechanisms underlying these anti-diabetic effects remain unclear. In this study, we examined the anti-diabetic activity of silk fibroin hydrolysate (SFH) in C57BL/KsJ-db/db (db/db) mice, a well-known animal model of non-insulin dependent diabetes mellitus. When the db/db mice were administered SFH in drinking water for 6 weeks, hyperglycemia in the animals gradually disappeared and the level of glycosylated hemoglobin decreased, indicating that SFH plays important role in reducing the symptoms of diabetes. In addition, SFH-treated db/db mice exhibited improved glucose tolerance with increased plasma insulin levels. Immunohistochemical and morphological analyses showed that SFH up-regulated insulin production by increasing pancreatic beta cell mass in the mice. In summary, our results suggest that SFH exerts anti-diabetic effects by increasing pancreatic beta cell mass in a non-insulin dependent diabetes mellitus mouse model.
Animals ; Diabetes Mellitus ; Drinking Water ; Fibroins ; Glucose ; Hemoglobin A, Glycosylated ; Hyperglycemia ; Insulin ; Insulin-Secreting Cells ; Medicine, East Asian Traditional ; Mice ; Models, Animal ; Plasma ; Silk

Background: Inbred mice have several advantages, including genetic similarity to humans, a well-established gene manipulation system, and strong tolerance to inbreeding. However, inbred mice derived from a limited genetic pool have a small genetic diversity. Thus, the development of new inbred strains from wild mice is needed to overcome this limitation. Hence, in this study, we used a new strain of inbred mice called KWM/Hym. We sequenced the Mx1 gene to elucidate the genetic diversities of KWM/Hym mice and observed the biological alterations of the Mx1 protein upon influenza A infection. Results: The Mx1 gene in KWM/Hym mice had 2, 4, and 38 nucleotide substitutions compared to those in the Mx1 gene in A2G, CAST/EiJ, and Mus spretus mice, respectively. Moreover, the Mx1 protein in KWM/Hym mice had 2 and 25 amino acid substitutions compared to those in the Mx1 protein in CAST/EiJ and M. spretus mice, respectively. To elucidate the function of the Mx1 protein, we inoculated the influenza A virus (A/WSN/1933) in KWM/Hym mice. Nine days after infection, all infected KWM/Hym mice survived without any weight loss. Four days after infection, the lungs of the infected KWM/Hym mice showed mild alveolitis and loss of bronchiolar epithelium; however, the pulmonary viral titers of the infected KWM/Hym mice were significantly lower than that in the infected BALB/c mice (2.17 × plaqueforming units mL −1 ). Conclusions Our results demonstrate that the KWM/Hym mice are resistant to influenza A virus infection. Further, these mice can be used as a model organism to understand the mechanism of influenza A virus susceptibility.