RESUMO
CtBP/BARS is a unique protein family in having quite diversified cellular functions, intercellular localizations, and developmental roles. ANGUSTIFOLIA (AN) is the sole homolog of CtBP/BARS from Arabidopsis thaliana, although it has plant AN-specific motifs and a long C-terminus. Previous studies suggested that AN would function in the nucleus as a transcriptional co-repressor, as CtBPs function in animals; however, precise verification has been lacking. In this paper, we isolated a homologous gene (MAN) of AN from liverwort, Marchantia polymorpha. Transformation of the Arabidopsis an-1 mutant with 35S-driven MAN completely complemented the an-1 phenotype, although it lacks the putative nuclear localization signal (NLS) that exists in AN proteins isolated from other plant species. We constructed several plasmids for expressing modified ANs with amino acid substitutions in known motifs. The results clearly indicated that modified AN with mutations in the putative NLS-like domain could complement the an-1 phenotype. Therefore, we re-examined localization of AN using several techniques. Our results demonstrated that AN localizes on punctuate structures around the Golgi, partially overlapping with a trans-Golgi network resident, which highlighted an unexpected link between leaf development and membrane trafficking. We should reconsider the roles and evolutionary traits of AN based on these findings.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Marchantia/genética , Proteínas Repressoras/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Substituição de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Núcleo Celular/genética , Genes de Plantas , Genes Reporter , Teste de Complementação Genética , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Marchantia/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Meristema/metabolismo , Meristema/ultraestrutura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Mutação , Sinais de Localização Nuclear/metabolismo , Fenótipo , Células Vegetais/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/genética , Especificidade da Espécie , Transformação Genética , Rede trans-Golgi/metabolismo , Rede trans-Golgi/ultraestruturaRESUMO
We report a case of bone marrow carcinomatosis originating from breast cancer that was treated with weekly paclitaxel (PTX). A 42-year-old female patient underwent mastectomy with axillary lymph node dissection for breast cancer in 2001. Multiple bone metastases were diagnosed in 2008, but she remained stable with chemotherapy and hormonal therapy for about two years. In 2010, thrombocytopenia occurred, and she was diagnosed with bone marrow carcinomatosis after bone marrow biopsy. She was treated with weekly PTX(80 mg/m2), and recovered successfully after treatment. About one year has elapsed since initiation of therapy, and there has been no recurrence. Bone marrow carcinomatosis originating from breast cancer is very rare, and is regarded as a disease with a poor prognosis. However, weekly PTX could be a valid treatment for prolonging survival of bone marrow carcinomatosis originating from breast cancer.