Biomedical subjects

Cláudia Macedo

Publications and source records attributed to Cláudia Macedo.

2 recordsLinked to original sources

PubMed2004

A transcript finishing initiative for closing gaps in the human transcriptome.

We report the results of a transcript finishing initiative, undertaken for the purpose of identifying and characterizing novel human transcripts, in which RT-PCR was used to bridge gaps between paired EST clusters, mapped against the genomic sequence. Each pair of EST clusters selected for experimental validation was designated a transcript finishing unit (TFU). A total of 489 TFUs were selected for validation, and an overall efficiency of 43.1% was achieved. We generated a total of 59,975 bp of transcribed sequences organized into 432 exons, contributing to the definition of the structure of 211 human transcripts. The structure of several transcripts reported here was confirmed during the course of this project, through the generation of their corresponding full-length cDNA sequences. Nevertheless, for 21% of the validated TFUs, a full-length cDNA sequence is not yet available in public databases, and the structure of 69.2% of these TFUs was not correctly predicted by computer programs. The TF strategy provides a significant contribution to the definition of the complete catalog of human genes and transcripts, because it appears to be particularly useful for identification of low abundance transcripts expressed in a restricted set of tissues as well as for the delineation of gene boundaries and alternatively spliced isoforms.

Alternative Splicing↗

PubMed2003

Gene expression profiling during thymus ontogeny and its association with TCRVbeta8.1-Dbeta2.1 rearrangements of inbred mouse strains.

The V(D)J recombination of TCRalpha and beta in early developing T-cells is a highly modulated phenomenon initiated and completed by recombinase complex (RAG-1 and RAG-2), and regulated by other gene products such as interleukins. To further evaluate the association of several other gene products with the evolution of TCRVbeta8.1 V(D)J rearrangements in vivo, the mRNA expression levels of seven interleukins, three cytokines, receptors TCRVbeta8.1 and IL-2Rbeta, MHC-I/MHC-II, RAG-1/ RAG-2 and retroviral superantigen MMTV(SW) were measured by RT-PCR during the fetal development of the thymus of three inbred mouse strains (Balb-c, C57B1/6 and CBA/J). Clustering using the Tree View software, was used to organize these genes based on similarity of expression patterns. Each strain displayed a different expression profile during thymus ontogeny. During the late developmental stage the most evident association was the kinetics of MMTV(SW) retrovirus, IL-2Rbeta and IL-7 overexpression with reduction of TCRVbeta8.1-D1beta2.1 rearrangement in the thymus of CBA/J mice. These data suggest a susceptibility of this strain to expression of MMTV(SW) upon reduction of the rearranged TCRVbeta8.1-Dbeta2.1 segment in developing thymocytes, with parallel IL-7 overexpression.

Animals↗