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D M Kingsley

Publications and source records attributed to D M Kingsley.

At least 19 recordsLinked to original sources
PubMed2000

Efficient studies of long-distance Bmp5 gene regulation using bacterial artificial chromosomes.

The regulatory regions surrounding many genes may be large and difficult to study using standard transgenic approaches. Here we describe the use of bacterial artificial chromosome clones to rapidly survey hundreds of kilobases of DNA for potential regulatory sequences surrounding the mouse bone morphogenetic protein-5 (Bmp5) gene. Simple coinjection of large insert clones with lacZ reporter constructs recapitulates all of the sites of expression observed previously with numerous small constructs covering a large, complex regulatory region. The coinjection approach has made it possible to rapidly survey other regions of the Bmp5 gene for potential control elements, to confirm the location of several elements predicted from previous expression studies using regulatory mutations at the Bmp5 locus, to test whether Bmp5 control regions act similarly on endogenous and foreign promoters, and to show that Bmp5 control elements are capable of rescuing phenotypic effects of a Bmp5 deficiency. This rapid approach has identified new Bmp5 control regions responsible for controlling the development of specific anatomical structures in the vertebrate skeleton. A similar approach may be useful for studying complex control regions surrounding many other genes important in embryonic development and human disease.

Animals↗
PubMed1999

GDF5 coordinates bone and joint formation during digit development.

A functional skeletal system requires the coordinated development of many different tissue types, including cartilage, bones, joints, and tendons. Members of the Bone morphogenetic protein (BMP) family of secreted signaling molecules have been implicated as endogenous regulators of skeletal development. This is based on their expression during bone and joint formation, their ability to induce ectopic bone and cartilage, and the skeletal abnormalities present in animals with mutations in BMP family members. One member of this family, Growth/differentiation factor 5 (GDF5), is encoded by the mouse brachypodism locus. Mice with mutations in this gene show reductions in the length of bones in the limbs, altered formation of bones and joints in the sternum, and a reduction in the number of bones in the digits. The expression pattern of Gdf5 during normal development and the phenotypes seen in mice with single or double mutations in Gdf5 and Bmp5 suggested that Gdf5 has multiple functions in skeletogenesis, including roles in joint and cartilage development. To further understand the function of GDF5 in skeletal development, we assayed the response of developing chick and mouse limbs to recombinant GDF5 protein. The results from these assays, coupled with an analysis of the development of brachypodism digits, indicate that GDF5 is necessary and sufficient for both cartilage development and the restriction of joint formation to the appropriate location. Thus, GDF5 function in the digits demonstrates a link between cartilage development and joint development and is an important determinant of the pattern of bones and articulations in the digits.

Animals↗
PubMed1998

An extensive 3' regulatory region controls expression of Bmp5 in specific anatomical structures of the mouse embryo.

Bone morphogenetic proteins (BMPs) are secreted signaling molecules that control important developmental events in many different organisms. Previous studies have shown that BMPs are expressed at the earliest stages of skeletal development, and are required for formation of specific skeletal features, strongly suggesting that they are endogenous signals used to control formation of skeletal tissue. Despite the importance of BMP signaling in normal development, very little is known about the mechanisms that control the synthesis and distribution of BMP signals in vertebrates. Here, we identify a large array of cis-acting control sequences that lay out expression of the mouse Bmp5 gene in specific skeletal structures and soft tissues. Some of these elements show striking specificity for particular anatomical features within the skeleton, rather than for cartilage and bone in general. These data suggest that the vertebrate skeleton is built from the sum of many independent domains of BMP expression, each of which may be controlled by separate regulatory elements driving expression at specific anatomical locations. Surprisingly, some of the regulatory sequences in the Bmp5 gene map over 270 kb from the Bmp5 promoter, making them among the most distant elements yet identified in studies of eukaryotic gene expression.

Alleles↗
PubMed1997

Spectrum of Bmp5 mutations from germline mutagenesis experiments in mice.

Over 40 years of mutagenesis experiments using the mouse specific-locus test have produced a large number of induced germline mutations at seven loci, among them the short ear locus. We have previously shown that the short ear locus encodes bone morphogenetic protein 5 (BMP5), a member of a large family of secreted signaling molecules that play key roles in axis formation, tissue differentiation, mesenchymalepithelial interactions, and skeletal development. Here we examine 24 chemical- and radiation-induced mutations at the short ear locus. Sequence changes in the Bmp5 open reading frame confirm the importance of cysteine residues in the function of TGF beta superfamily members. The spectrum of N-ethyl-N-nitrosourea-induced mutations also provides new information about the basepair, sequence context, and strand specificity of germline mutations in mammals.

Amino Acid Sequence↗
PubMed1996

Mechanical and geometric changes in the growing femora of BMP-5 deficient mice.

We examined the growth-related changes in femoral geometry and torsional strength in BMP-5 deficient short-ear mice over a 22-week time interval ("long-term" changes). Four groups of female mice (n = 6 per group) were examined: short-ear animals and their heterozygous control littermates at 4 and 26 weeks of age. In agreement with findings previously observed in a mixed-gender group of adult mice (26 weeks), the femora of short-ear animals were significantly smaller in length and cross section at both ages. The magnitudes of the differences between genotypes were comparable at each age, indicating that the overall rates of appositional and endochondral growth were similar for both genotypes over the 22-week period. In the adult animals, short-ear femora were 27 +/- 7% weaker in torsional strength due to their smaller cross-sectional geometry. However, bone strength in adult short-ear mice appeared to be adequate for animal size: No significant difference was detected in maximum femoral torque when normalized by body mass. In 4-week old animals, BMP-5 deficiency was associated with a 27 +/- 6% lower body mass, but the torsional strength of the femur was not significantly different from that of controls. Cross-sectional geometry was smaller in 4-week old short-ear mice, but the apparent bone material ultimate shear stress was elevated by 33 +/- 10%, thereby resulting in a whole bone torsional strength equivalent to that of the larger control mice. While the data suggest a higher material strength in the 4-week-old short-ear animals, no significant difference in the level of bone mineralization was detectable between genotypes at either age.

Analysis of Variance↗
PubMed1996

Joint patterning defects caused by single and double mutations in members of the bone morphogenetic protein (BMP) family.

The mouse brachypodism locus encodes a bone morphogenetic protein (BMP)-like molecule called growth/differentiation factor 5 (GDF5). Here we show that Gdf5 transcripts are expressed in a striking pattern of transverse stripes within many skeletal precursors in the developing limb. The number, location and time of appearance of these stripes corresponds to the sites where joints will later form between skeletal elements. Null mutations in Gdf5 disrupt the formation of more than 30% of the synovial joints in the limb, leading to complete or partial fusions between particular skeletal elements, and changes in the patterns of repeating structures in the digits, wrists and ankles. Mice carrying null mutations in both Gdf5 and another BMP family member, Bmp5, show additional abnormalities not observed in either of the single mutants. These defects include disruption of the sternebrae within the sternum and abnormal formation of the fibrocartilaginous joints between the sternebrae and ribs. Previous studies have shown that members of the BMP family are required for normal development of cartilage and bone. The current studies suggest that particular BMP family members may also play an essential role in the segmentation process that cleaves skeletal precursors into separate elements. This process helps determine the number of elements in repeating series in both limbs and sternum, and is required for normal generation of the functional articulations between many adjacent structures in the vertebrate skeleton.

Animals↗
PubMed1995

Chromosomal localization, embryonic expression, and imprinting tests for Bmp7 on distal mouse chromosome 2.

Murine Bmp7 has been assigned to distal Chromosome 2 by interspecific backcross mapping. The map location suggests close linkage to classical mouse mutations and places Bmp7 within a chromosome region thought to contain one or more unidentified imprinted genes. A direct test suggests that Bmp7 is not imprinted. An examination of embryonic RNA expression patterns shows that Bmp7 is expressed in a variety of skeletal and nonskeletal tissues. Both embryonic expression patterns and the human chromosomal sublocalization inferred from its mouse location make Bmp7 a candidate for the gene affected in some patients with Holt-Oram syndrome.

Animals↗
PubMed1995

The mouse Snell's waltzer deafness gene encodes an unconventional myosin required for structural integrity of inner ear hair cells.

The mouse represents an excellent model system for the study of genetic deafness in humans. Many mouse deafness mutants have been identified and the anatomy of the mouse and human ear is similar. Here we report the use of a positional cloning approach to identify the gene encoded by the mouse recessive deafness mutation, Snell's waltzer (sv). We show that sv encodes an unconventional myosin heavy chain, myosin VI, which is expressed within the sensory hair cells of the inner ear, and appears to be required for maintaining their structural integrity. The requirement for myosin VI in hearing makes this gene an excellent candidate for a human deafness disorder.

Amino Acid Sequence↗
PubMed1995

Long bone geometry and strength in adult BMP-5 deficient mice.

Bone morphogenetic proteins (BMPs) play a critical role in early skeletal development. BMPs are also potential mediators of bone response to mechanical loading, but their role in later stages of bone growth and adaptation has yet to be studied. We characterized the postcranial skeletal defects in mature mice with BMP deficiency by measuring hind-limb muscle mass and long bone geometric, material, and torsional mechanical properties. The animals studied were 26-week-old short ear mice (n = 10) with a homozygous deletion of the BMP-5 gene and their heterozygous control litter mates (n = 15). Gender-related effects, which were found to be independent of genotype, were also examined. The femora of short ear mice were 3% shorter than in controls and had significantly lower values of many cross-sectional geometric and structural strength parameters (p < 0.05). No significant differences in ash content or material properties were detected. Lower femoral whole bone torsional strength was due to the smaller cross-sectional geometry (16% smaller section modulus) in the short ear mice. The diminished cross-sectional geometry may be commensurate with lower levels of in vivo loading, as reflected by body mass (-8%) and quadriceps mass (-11%). While no significant gender differences were found in whole bone strength or cross-sectional geometry, males had significantly greater body mass (+18%) and quadriceps mass (+15%) and lower tibio-fibular ash content (-3%). The data suggest that adult female mice have a more robust skeleton than males, relative to in vivo mechanical demands. Furthermore, although the bones of short ear mice are smaller and weaker than in control animals, they appear to be biomechanically appropriate for the in vivo mechanical loads that they experience.

Analysis of Variance↗
PubMed1994

Limb alterations in brachypodism mice due to mutations in a new member of the TGF beta-superfamily.

The mutation brachypodism (bp) alters the length and number of bones in the limbs of mice but spares the axial skeleton. It illustrates the importance of specific genes in controlling the morphogenesis of individual skeletal elements in the tetrapod limb. We now report the isolation of three new members of the transforming growth factor-beta (TGF-beta) superfamily (growth/differentiation factors (GDF) 5,6 and 7) and show by mapping, expression patterns and sequencing that mutations in Gdf5 are responsible for skeletal alterations in bp mice. GDF5 and the closely related GDF6 and GDF7 define a new subgroup of factors related to known bone- and cartilage-inducing molecules, the bone morphogenetic proteins (BMPs). Studies of Bmp5 mutations in short ear mice have shown that at least one other BMP gene is also required for normal skeletal development. The highly specific skeletal alterations in bp and short ear mice suggest that different members of the BMP family control the formation of different morphological features in the mammalian skeleton.

Amino Acid Sequence↗
PubMed1994

BMP5 and the molecular, skeletal, and soft-tissue alterations in short ear mice.

Mutations at the mouse short ear (se) locus alter the formation and repair of skeletal structures and the development of several soft tissues. Most of the developmental effects of the gene have been studied using a spontaneous mutation reported over 70 years ago. Here we show that this mutation consists of a nonsense mutation in a secreted signaling molecule called bone morphogenetic protein 5 (BMP5). This small sequence alteration, in combination with previously reported translocation and deletion mutations, provides strong genetic evidence that BMP5 is the normal product of the se locus. Transcripts from the Bmp5 gene are expressed at the earliest stages of normal skeletal development in patterns that closely resemble the shapes of forming skeletal elements. The gene is also expressed at several sites of soft tissue abnormalities previously reported in se animals, including lungs, liver, ureter, bladder, and intestines. The combined genetic, biochemical, and expression data suggest that BMP5 is a key signal used to initiate formation of particular skeletal elements and is required for normal development of several soft tissues as well.

Abnormalities, Multiple↗
PubMed1994

What do BMPs do in mammals? Clues from the mouse short-ear mutation.

Bone morphogenetic proteins (BMPs) are a family of secreted signaling molecules that were originally isolated on the basis of their remarkable ability to induce the formation of ectopic bones when implanted into adult animals. The first mutations identified in a mammalian BMP gene suggest that members of this family induce the formation, patterning and repair of particular morphological features in higher animals.

Animals↗
PubMed1992

The mouse short ear skeletal morphogenesis locus is associated with defects in a bone morphogenetic member of the TGF beta superfamily.

The mouse short ear gene is required for normal growth and patterning of skeletal structures, and for repair of bone fractures in adults. We have carried out an extensive chromosome walk in the chromosome region that surrounds this locus. Here we show that the short ear region contains the gene for a TGF beta-related protein called bone morphogenetic protein 5 (Bmp-5). This gene is deleted or rearranged in several independent mutations at the short ear locus. Mice homozygous for large deletions of the Bmp-5 coding region are viable and fertile. Mutations at the short ear locus provide an important new tool for defining the normal functions of BMPs in mammals. The specific skeletal defects seen in short-eared animals, which occur against a background of otherwise normal skeletal structures, suggest that particular aspects of skeletal morphology may be determined by individual members of a family of signaling factors that can induce the formation of cartilage and bone in vivo.

Animals↗