PubMed Health⌕ Search

Biomedical subjects

M González-Moreno

Publications and source records attributed to M González-Moreno.

6 recordsLinked to original sources

Bringing gene order into bacterial shape.

A different arrangement of a cluster of genes involved in division and cell-wall synthesis separates bacilli from other bacteria in a phylogenetic analysis. We conclude that the relationships between these genes are not random and might reflect significant events in the evolution of the coupling between growth and division in bacteria.

Bacteria↗

Thyrotropin-like immunoreactivity in the developing chicken retina.

In this paper we analysed the presence and localisation of thyrotropin during retinal development in Gallus domesticus. Specific thyrotropin-like immunohistochemical staining was observed from the beginning of the second incubation week to one day post-hatching in chicken retina. Thyrotropin is a 28.3 KDa glycoprotein, synthesised by the anterior pituitary gland, and it is implicated in the stimulation of the synthesis and release of thyroid hormones. Until now, the action of thyrotropin has been established exclusively in hormonal terms. Recently, this glycoprotein has been localised in synaptic processes in the human retina by using a specific antiserum (Fdez-Trujillo et al., 1995). To the best of our knowledge this report is the first time that thyrotropin has been immunocytochemically demonstrated in the chicken retina. The pattern of thyrotropin-like immunoreactivity suggests that this glycoprotein could act as modulator of synaptic transmission, but it may also play a much broader role in regulating trophic functions.

Animals↗

Identification of a mammalian homologue of the fungal Tom70 mitochondrial precursor protein import receptor as a thyroid hormone-regulated gene in specific brain regions.

Thyroid hormone is an important regulator of mammalian brain maturation. By differential display PCR, we isolated a cDNA clone (S2) that is specifically up-regulated in the striatum of neonatal hypothyroid rats. S2 was identified as KIAA0719, the first human gene distantly homologous to the fungal Tom70, which encodes a member of the translocase mitochondrial outer membrane complex involved in the import of preproteins into the mitochondria. By northern and in situ hybridization studies, KIAA0719 was found to be up-regulated in the striatum, nucleus accumbens, and discrete cortical layers of 15-day-old hypothyroid rats. In contrast, lower expression was found in the olfactory tubercle, whereas no differences were detected in other brain regions. Significantly, treatment of hypothyroid animals with single injections of thyroxine restored the normal levels of KIAA0719 expression. Moreover, treatment of control animals with thyroxine led to a reduced expression, demonstrating a negative hormonal regulation in vivo. Thus, KIAA0719 gene expression is regulated by thyroid hormone in the neonatal rat brain in a region-specific fashion. Given the role of the homologous Tom70 gene, the alteration of KIAA0719 expression may contribute to the changes in mitochondrial morphology and physiology caused by hypothyroidism in the developing rat brain.

Amino Acid Sequence↗

Presence and distribution of 5HT-, VIP-, NPY-, and SP-immunoreactive structures in adult mouse lung.

A large number of biologically active substances have been identified and characterised in the respiratory tract of several mammals. These substances (amines and peptides) exert important regulatory influences on respiratory functions, and they act as neurotransmitters/neuromodulators, both being released from nerve terminals as neuroendocrine cells. However, these substances can also have other effects which suggest a paracrine action. Thus, to understand the role of amines and peptides in the lung, it is important to explore their localisation in different species. By using immunocytochemical staining methods we have studied the morphology and distribution of serotonin-, Substance P-, neuropeptide Y- and VIP-like immunoreactivity in the adult mouse lung. Moreover a pretreatment with colchicine, pargyline and 5-hydroxytryptophan as staining enlargement method was made. A widespread distribution of isolated endocrine cells and neuro-epithelial bodies containing 5HT-like immunoreactivity was recorded within the lung. NPY-like immunoreactive nerve fibres were localised in the airway smooth muscle and surrounding the blood vessels. VIP-like immunoreactivity was revealed in single cells as well as in some nerve fibres and ganglia around the blood vessels and in the bronchial smooth muscle. SP-like IR was observed in nerve fibres located in the smooth muscle of the airways, surrounding bronchi and bronchioli but not next to the intrapulmonary blood vessels. Their localisation both in cells and nerve fibres of the respiratory system suggests that they play a role in the regulatory function of the mouse respiratory tract, exerting their influence by endocrine, paracrine, neurosecretory pathways or a combination of all of these.

Animals↗