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M Peyrard

Publications and source records attributed to M Peyrard.

At least 37 records · Page 2Linked to original sources
PubMed1996

Characterization of a second human clathrin heavy chain polypeptide gene (CLH-22) from chromosome 22q11.

We report cloning and characterization of the second human clathrin heavy chain polypeptide gene (CLH-22) localized to chromosome 22q11. Hence H. sapiens is the first species for which two clathrin heavy chain genes have been reported. We provide 5470 bp cDNA sequence covering the entire open reading frame of the CLH-22 gene. The predicted polypeptide is composed of 1640 amino acids. Its 6 kb transcript is expressed in all of 16 tested human tissues, suggesting it is a housekeeping gene. Skeletal muscle, testis and heart show significantly higher expression levels. Compared to the previously characterized human clathrin heavy chain gene localized on chromosome 17 (CLH-17), CLH-22 shows different transcript size and expression profile in human tissues. Northern analysis of CLH-22 suggests that several alternatively spliced transcripts exist. A presumably single, 171 bp long alternatively spliced exon has been characterized. Amino acid sequence comparison between CLH-22 and CLH-17 shows an overall identify and similarity of 84.7 and 91.1%, respectively. At the nucleic acid level, identity between open reading frames of both genes is 74.3%. Sequence comparison with previously cloned genes in other species suggests that counterparts of the CLH-17 gene have been cloned in B. taurus and R. norvegicus, whereas presumptive mammalian homologues of the CLH-22 gene are yet to be characterized. Our Northern and Southern blot analyses of meningiomas clearly suggest the CLH-22 gene may be involved in the tumor development and can be considered as a candidate for a tumor suppressor.

Alternative Splicing↗
PubMed1994

Deletions on chromosome 22 in sporadic meningioma.

Meningiomas are the second most common group of primary central nervous system tumors in humans. Cytogenetic and molecular studies imply that genes involved in the primary development of meningioma reside on chromosome 22. The recently characterized neurofibromatosis type 2 gene (NF2) has been shown to be mutated in two cases of sporadic meningioma, suggesting that this is the chromosome 22 gene which is involved in tumorigenesis. We have investigated a series of 170 meningiomas by deletion mapping analysis with 43 markers from chromosome 22 to ascertain if NF2 is the only gene on this autosome that is inactivated. Half of the tumors showed results consistent with monosomy for chromosome 22, whereas 13 cases showed terminal deletions of 22q, including the NF2 region. Homozygous (complete) deletions were detected in tumors from two patients. In one of them complete loss was found at the NF2 locus and cosmid contigs from the region were used to determine the extent of the deletions. The second tumor showed homozygous loss of two large genomic regions outside the NF2 region. These aberrations were confined to only one part of this large tumor, suggesting that they may be involved in the later stages of meningioma development. An additional four tumors had interstitial deletions on chromosome 22, in three of them without overlap with NF2. Our results show that NF2 is completely inactivated in sporadic meningioma but do not rule out the possibility that additional chromosome 22 loci are important in tumorigenesis.

Base Sequence↗
PubMed1994

Characterization of a new member of the human beta-adaptin gene family from chromosome 22q12, a candidate meningioma gene.

A 140 kb homozygous deletion from 22q12 in one meningioma directed us towards the cloning and characterization of a new member of the human beta-adaptin gene family (named BAM22). Adaptins are essential for the formation of clathrin coated vesicles in the course of intracellular transport of receptor-ligand complexes. The BAM22 gene is totally inactivated in the tumor with homozygous deletion. Northern blot analysis of 70 sporadic meningiomas showed specific loss of expression in 8 tumors, suggesting inactivation of BAM22. Based on this, we propose BAM22 as a second chromosome 22 locus important in meningioma development, after the neurofibromatosis type 2 gene.

Adaptor Protein Complex 1↗
PubMed1993

Cloning of a novel, anonymous gene from a megabase-range YAC and cosmid contig in the neurofibromatosis type 2/meningioma region on human chromosome 22q12.

In order to permit detailed characterization of meningioma cases showing deletions within chromosomal band 22q12 and further systematically clone genes located within this region, we established a genomic YAC and cosmid contig which encompasses a region in excess of 1000 kb of 22q12. The YAC contig consists of 6 YAC clones arranged into 5 overlapping steps covering more than 1100 kb. Two corresponding cosmid contigs consisting of 40 steps of overlapping groups of cosmids encompasses 900-1000 kb. This set of genomic clones provides a detailed physical map of this part of chromosome 22 and constitutes a basis for the isolation and characterization of genes that may be located within this chromosomal region. Employing the exon-amplification method on two cosmids from the contig, we cloned a novel, anonymous gene, pK1.3, which potentially encodes a protein of 683 amino acids with a predicted molecular weight of of 78.5 kD. Its 2.7 kb mRNA is expressed ubiquitously. We estimated the genomic size of this gene to 100-150 kb, and it is located in the immediate centromeric vicinity of the neurofibromatosis 2 (NF2) tumor suppressor gene.

Amino Acid Sequence↗