RESUMO
We have studied the morphology and vein branching of rosette leaves in Arabidopsis thaliana mutants as and sa, which proved to be alleles of the A. thaliana AS1 and AS2 genes, respectively. We have also analyzed the localization of bioactive auxin, as measured by the expression of the DR5::GUS transgene, as well as the expression patterns of BP, as measured by the expression of the BP::GUS transgene in leaves of the mutants. In mature leaves of the mutants, BP was expressed ectopically. Furthermore, the mutants showed some defects in the localization and concentration of free auxin compared to the wild type. Our results of studying new alleles of AS1 and AS2 support their role in control of class I KNOX genes and auxin transport.
Assuntos
Alelos , Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Mutação , Organogênese/fisiologia , Folhas de Planta/embriologia , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Ácidos Indolacéticos/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/embriologia , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genéticaRESUMO
A new deletion allele of the APETALA1 (AP1) gene encoding a type II MADS-box protein with the key role in the initiation of flowering and development of perianth organs has been identified in A. thaliana. The deletion of seven amino acids in the conserved region of the K domain in the ap1-20 mutant considerably delayed flowering and led to a less pronounced abnormality in the corolla development compared to the ap1-3 and apl-6 alleles with low and medium expression, respectively. At the same time, a considerable stamen reduction has been revealed in ap1-20 as distinct from ap1-3 and ap1-6 alleles. These data indicate that the K domain of AP1 can be crucial for the initiation of flowering and expression regulation of B-class genes controlling stamen development.
Assuntos
Alelos , Sequência de Aminoácidos/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Domínio MADS/genética , Deleção de Sequência , Estrutura Terciária de Proteína/genéticaRESUMO
The nucleotide sequence was analyzed for the temperature-sensitive allele abruptus (abr), which distorts polar auxin transport (PAT) in the floral shoot. The mutation C-->T was found in the second exon and led to an amino acid substitution (glycin-->glutamic acid) in the conserved domain of protein kinase encoded by the ABRUPTUS/PINOID (ABR/PID) gene. RT--PCR revealed a 100-fold decrease in transcription of the LEAFY (LFY) gene in the abr mutant with high expressiveness of the mutant character; transcription of the fused LFY::GUS gene was also low in the mutant. The results agree with data of the phenotypic analysis of the abr lfy double mutant and testify to an important role of auxin gradients in regulating expression of the LFY gene.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Brotos de Planta/genética , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição/genética , Substituição de Aminoácidos , Arabidopsis/metabolismo , Transporte Biológico/genética , Éxons/genética , Ácidos Indolacéticos/metabolismo , Brotos de Planta/metabolismo , Mutação PuntualRESUMO
Using the data on mitochondrial DNA (mtDNA) polymorphism, genetic structures of the ethnic groups inhabiting South and East Siberia, including Altaians, Buryats, Tuvinians, Todjins, Tofalars, Yakuts, and Evenks were described. Mitochondrial gene pools of the populations examined were characterized by different ratios between Mongoloid (M*, C, D, E/G, G, A, B, and F) and Caucasoid (H, HV, I, J, K, T, U, and X) mtDNA lineages. All the populations studied carried a marked Mongoloid component, maximum frequency of which was observed in Evenks (92.4%) and Buryats (90.1%). Maximum frequencies of Caucasoid mtDNA lineages were detected in Tofalars (20.7%) and Yakuts (14.5%). Statistically significant interpopulation differences regarding the frequencies of mtDNA haplogroups were observed between all populations examined, excluding the pairs of Evenks-Yakuts, Evenks-Tuvinians, and Tuvinians-Todjins. Differentiation of the ethnic groups inhabiting South and East Siberia, as well as Central and Middle Asia, is discussed based on genetic, linguistic, and anthropological data.
Assuntos
DNA Mitocondrial , Genética Populacional , Polimorfismo Genético , Povo Asiático/genética , Variação Genética , Humanos , Filogenia , Sibéria/etnologia , População Branca/genéticaRESUMO
Using the data on five biallellic Y-chromosome loci (DYS199, 92R7, SRY1532, RBF5 and DYS287) polymorphism, genetic structures of the five Turkic-speaking ethnic groups of the Altai-Sayan highland (Tuvinians, Sojots, Shorians, Khakassians, and Southern Altaians (Altai-Kizhi), were described. The gene pools of the populations examined were characterized by the presence of pronounced paleo-Caucasoid component (92R7-T-lineages). The frequency of this component increased westward, reaching more than 70% in Shorians and Southern Altaians. Haplotype TAT-C (RBF5 locus) was observed in all populations, except Shorians, with the frequencies varying from 5.4% in Altai-Kizhi to 18.8% in Khakassians. The Alu-insertion in the DYS287 locus was revealed only in the Altaian sample with the frequency of 3.3%. It was established that the Altai-Sayan populations studied split into two statistically significantly different groups. One of the groups was represented by Tuvinians, Sojots, and Khakassians, while another one was comprised of Shorians and Altaians.
