Insect metamorphosis is induced by the steroid 20-hydroxyecdysone (20E) in the absence of sesquiterpenoid juvenile hormone (JH). In Drosophila melanogaster, the Broad-Complex (BR-C) transcriptional factor plays critical roles during metamorphosis. We isolated cDNAs encoding BR-C in the silkworm Bombyx mori and examined their mRNA expression. cDNAs for three BR-C isoforms with zinc finger pairs (Z1, Z2 and Z4) and four isoforms lacking them were cloned. Their mRNAs were expressed in multiple tissues at the larval-pupal metamorphosis. In the anterior silk gland, BR-C mRNAs were expressed at the end of the last larval instar but not expressed during the penultimate instar. 20E administration induced BR-C mRNA expression and JH suppressed 20E-induced BR-C expression in this tissue both in vivo and in vitro. Thus, BR-C mRNAs are inducible by 20E only in the absence of JH, a finding that explains their metamorphosis-specific expression.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cbpc.2004.09.009 | DOI Listing |
DNA Res
January 2025
School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
Pontederia cordata L. is an aquatic ornamental plant native to the Americas, but has been widely distributed in South Asia, Australia, and Europe. The genetic mechanisms behind its rapid adaptation and spread have not yet been well understood.
View Article and Find Full Text PDFMol Biol Evol
January 2025
Laboratório de Algoritmos em Biologia, Departamento de Genética, Ecologia e Evolução, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil.
A key trait of Eukarya is the independent evolution of complex multicellular (CM) in animals, plants, fungi, brown algae and red algae. This phenotype is characterized by the initial exaptation of cell-cell adhesion genes followed by the emergence of mechanisms for cell-cell communication, together with the expansion of transcription factor gene families responsible for cell and tissue identity. The number of cell types (NCT) is commonly used as a quantitative proxy for biological complexity in comparative genomics studies.
View Article and Find Full Text PDFiScience
February 2025
Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China.
Pattern recognition receptors (PRRs), consisting of Toll-like receptors, RIG-I-like receptors, cytosolic DNA sensors, and NOD-like receptors, sense exogenous pathogenic molecules and endogenous damage signals to maintain physiological homeostasis. Upon activation, PRRs stimulate the sensitization of nuclear factor κB, mitogen-activated protein kinase, TANK-binding kinase 1-interferon (IFN) regulatory factor, and inflammasome signaling pathways to produce inflammatory factors and IFNs to activate Janus kinase/signal transducer and activator of transcription signaling pathways, resulting in anti-infection, antitumor, and other specific immune responses. Palmitoylation is a crucial type of post-translational modification that reversibly alters the localization, stability, and biological activity of target molecules.
View Article and Find Full Text PDFJOR Spine
March 2025
SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases) Santiago University Clinical Hospital Santiago de Compostela Spain.
Background: Intervertebral disc degeneration (IVDD) is one of the main causes of chronic low back pain. The degenerative process is often initiated by an imbalance between catabolic and anabolic pathways. Despite the large socio-economic impact, the initiation and progress of disc degeneration are poorly understood.
View Article and Find Full Text PDFFront Plant Sci
January 2025
National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, China.
Nitrogen deficiency is a key constraint on crop yield. Cassava, the world's sixth-largest food crop and a crucial source of feed and industrial materials, can thrive in marginal soils, yet its yield is still significantly affected by limited nitrogen availability. Investigating cassava's response mechanisms to nitrogen scarcity is therefore essential for advancing molecular breeding and identifying nitrogen-efficient varieties.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!