RESUMEN
Anti-HLA class I monoclonal antibody 01.65 inhibits the proliferative response of PHA-activated human T lymphocytes from peripheral blood mononuclear cells. The recruitment rate in the cell cycle is slack and the G1 and S phases are prolonged. Among the early events after PHA activation, only the calcium-dependent PKC activity appears to be modified: particulate PKC is completely depleted while cytosolic residual PKC is reduced by 80% after MAb 01.65 treatment. We have carried out in greater detail the study of c-myc gene regulation by MAb 01.65 and the results are as follows: (i) c-myc RNA transcription is normally initiated and finished, suggesting a post-transcriptional regulation of c-myc gene expression; (ii) no alteration in c-myc mRNA stability has been documented; (iii) steady-state levels of c-myc mRNA expression by Northern blot analysis and PCR amplification are decreased in the cytoplasmic compartment, while in the nuclear compartment they appear to be increased. Nuclear accumulation of mature mRNA after MAb 01.65 and PKC inhibitor (H7 and StSp) treatment appears to be the most probable mechanism involved. The possible implications of this are discussed.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Núcleo Celular/metabolismo , Genes myc , Antígenos de Histocompatibilidad Clase I/inmunología , Activación de Linfocitos , Proteínas Proto-Oncogénicas c-myc/biosíntesis , ARN Mensajero/biosíntesis , Linfocitos T/inmunología , Linfocitos T/metabolismo , Transcripción Genética , Secuencia de Bases , Células Cultivadas , Cartilla de ADN , Exones , Humanos , Fitohemaglutininas , Reacción en Cadena de la PolimerasaRESUMEN
Molecular defects and polymorphic haplotypes of coagulation factor VII gene were studied in eight unrelated Italian subjects with factor VII deficiency, seven having the factor VII- variant, one the factor VIIR variant. An intron 7 mutation, which alters the consensus donor splice site sequence, was found in six subjects. The presence of the founder effect is suggested by their common geographical origin (a mountain area in the Lazio region) and by the identical polymorphic haplotype underlying the mutation. A different mutation, also located in the 5' monomer of the repeated intron 7 sequence, was found in the heterozygous condition in a subject from Northern Italy. New polymorphic alleles were detected in the repeated intron 7 region in subjects from Eastern Africa. Two missense mutations in codon 97 (Gly-->Cys, Gly-->Ser), the first found in the compound heterozygous condition with the frequent intron 7 mutation, suggest the presence of a hot spot mutation site in the second epidermal growth factor domain. Two neutral dimorphisms at codon 333Ser and 115His were detected, the last in linkage disequilibrium with the 353Arg/Gln polymorphism, and showing differences in frequency in the FVII deficient and control subjects.
Asunto(s)
Deficiencia del Factor VII/genética , Frecuencia de los Genes , Mutación Puntual , Secuencia de Bases , Secuencia de Consenso , Análisis Mutacional de ADN , Femenino , Humanos , Intrones , Italia , Masculino , Datos de Secuencia Molecular , Linaje , Polimorfismo Genético , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo RestrictivoRESUMEN
A protein S gene polymorphism, detectable by restriction analysis of amplified exonic sequences, was investigated in a family with members affected by protein S deficiency, deep vein thrombosis and ictus. The clinical laboratory findings as well as RFLP analysis were consistent with the presence of a type WP III protein S deficiency clearly marked by a polymorphic allele, thus enabling us to determine the carrier status in several subjects. The RFLP analysis, extended to platelet mRNA after reverse transcription and amplification, demonstrated that the mRNA produced by the putative defective gene was present in a subject affected by thrombosis.
Asunto(s)
ADN/genética , Ictericia/genética , Proteína S/genética , ARN Mensajero/genética , Tromboflebitis/genética , Adulto , Secuencia de Bases , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Genético/genética , Polimorfismo de Longitud del Fragmento de Restricción , Deficiencia de Proteína SRESUMEN
We describe a polymorphism in the 5' region of the coagulation factor VII (FVII) gene, originating from a decanucleotide (CCTATATCCT) insert present in the less frequent allele. This marker can be detected by restriction analysis of polymerase chain reaction products.
Asunto(s)
Elementos Transponibles de ADN , Factor VII/genética , Polimorfismo Genético , Alelos , Secuencia de Bases , Cromosomas Humanos Par 13 , ADN/análisis , Frecuencia de los Genes , Genes Dominantes , Humanos , Datos de Secuencia Molecular , Oligonucleótidos , Regiones Promotoras GenéticasRESUMEN
The in situ hybridization technique was used for the localization on human chromosomes of single-copy and repeated sequences and, in addition, for the characterization of altered human chromosomes. Two anonymous clones, single or low-copy, obtained from a human X chromosome library were localized on the distal part of the long arm and in the paracentromeric region of X chromosome, respectively. A genomic fragment of the single-copy thyroglobulin (TG) gene was used to confirm the localization on the distal part of the long arm of chromosome 8. The localization and distribution on human chromosomes of the glyceraldehyde-3-phosphate dehydrogenase (GAPD) multigene family obtained by in situ hybridization and by somatic cell hybrids were compared. A phosphoglycerate kinase (PGK) c-DNA clone, which detects genic and pseudogenic sequences on the X chromosome, was used for the characterization of three small ring markers present in unrelated female patients.
