Video Experimental Relacionado
Updated: Aug 4, 2026
06:19
In situ Protocol for Butterfly Pupal Wings Using Riboprobes
Published on: May 28, 2007
Los genes homeóticos y la regulación y evolución del número de alas de los insectos
S B Carroll1, S D Weatherbee, J A Langeland
1Howard Hughes Medical Institute, Madison, Wisconsin, USA.
Nature
|May 4, 1995
Resumen
Las alas de los insectos evolucionaron sin la participación de genes homeóticos, cayendo más tarde bajo su control negativo. Esta investigación explora la base genética del desarrollo de las alas y sus implicaciones evolutivas en los insectos.
Área de la Ciencia:
- Biología del desarrollo evolutivo Biología del desarrollo evolutivo
- Genética La genética.
- Entomología Entomología.
Sus antecedentes:
- Las alas de los insectos son una innovación clave, impulsando la diversificación de más del 75% de las especies animales conocidas.
- La evidencia fósil indica que las alas evolucionaron a partir de segmentos de piernas, con los primeros insectos que poseían alas en múltiples segmentos del cuerpo.
- El diseño corporal de los pterigotos se diversificó más tarde, dando como resultado insectos con un número variable de pares de alas.
Objetivo del estudio:
- Investigar el papel de los genes homeóticos en la evolución de las alas de los insectos.
- Comprender los mecanismos genéticos subyacentes al desarrollo de las alas y su historia evolutiva.
Principales métodos:
- Examinando la función del gen homeótico en el desarrollo de las alas de Drosophila melanogaster.
- Analizando la expresión génica homeótica en un insecto apterygote primitivo.
Principales resultados:
- Los genes homeóticos no promueven la formación de alas, sino que más bien la reprimen en segmentos específicos del cuerpo.
- Diferentes genes homeóticos ejercen un control negativo sobre el desarrollo de las alas en segmentos distintos.
Conclusiones:
- Las alas probablemente se originaron independientemente de la regulación génica homeótica en un insecto ancestral.
- La evolución de las alas implicó la posterior incorporación de un control negativo por parte de genes homeóticos individuales durante la diversificación de las pterigotas.
Videos de Conceptos Relacionados
01:38Limits to Natural Selection
Organisms that are well-adapted to their environment are more likely to survive and reproduce. However, natural selection does not lead to perfectly adapted organisms. Several factors constrain natural selection.For one, natural selection can only act upon existing genetic variation. Hypothetically, redtusks may enhance elephant survival by deterring ivory-seeking poachers. However, if there are no gene variants—or alleles—for redtusks, natural selection cannot increase the prevalence of...
01:54Convergent Evolution
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.The structures that arise from convergent evolution are called analogous structures. They are similar in function even if they are dissimilar in structure. Further, structures can be analogous while also...
02:32Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
02:45The Ratio of X Chromosome to Autosomes
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
02:54Canonical Wnt Signaling Pathway
The gene encoding the main signaling molecules of the Wnt signaling pathways (the Wnt proteins) was discovered almost four decades ago by Nüsslein-Volhard and Wieschaus. They identified and originally named the gene "wingless" (wg) after a phenotype discovered during their landmark genetic screen in Drosophila for body pattern defects. At around the same time, another researcher named Harold Varmus found that a murine tumor virus activates the mammalian wg homolog, Int-1, which results in tumor...