Functional analysis of newly discovered growth control genes: experimental approaches

A large number of DNA sequences corresponding to human and animal transcripts have been filed in data banks, as cDNAs or ESTs (expression sequence tags). However, the actual function of their corresponding gene products is still largely unknown. Several of these genes may play a role in regulation of important biological processes such as cell division, differentiation, malignant transformation and oncogenesis. Elucidation of gene function is based on 2 main approaches, namely, overexpression and expression interference, which respectively mimick or suppress a given phenotype. The currently available tools and experimental approaches to gene functional analysis and the most recent advances in mass cDNA screening by functional analysis are discussed

Development of DNA probe for detection of Aujeszky's disease virus Desenvolvimento de uma sonda de DNA para a detecção do vírus da doença de Aujeszky

A DNA hybridization dot-blot assay using a radioactive and a non-radioactive probe has been developed for the detection of Aujeszky's disease virus (ADV). The Bam H I 7 fragment of ADV genomic DNA was labeled by nick translation using 32P-dCTP and the 196bp polymerase chain reaction (PCR) gG glycoprotein gene amplified fragment was also labeled by nick translation but using biotin d-7-dATP. This technique provides a fast and effective means of detecting acute cases of ADV infection but it was unable to detect ADV nucleic acid sequences in trigeminal nerve ganglia of latent infected pigs and mice.<br>Uma sonda radioativa e uma outra biotinilada foram produzidas para detecção do vírus da doença de Aujeszky (VDA). O fragmento de Bam H I 7 do DNA genômico do VDA foi marcado por "nick translation" empregando P32dCTP e um fragmento de 196pb, resultante de uma amplificação pela reação em cadeia pela polimerase marcado com biotina 7-dATP. Essas sondas, de uma maneira rápida e específica, prestaram-se para a detecção da infecção aguda pelo VDA. Entretanto, não se mostraram sensíveis o suficiente para detectar seqüências genômicas de VDA no gânglio trigêmio de suínos e camundongos com infecção latente