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PubMed2006

Phylogenetic comparison of protein-coding versus ribosomal RNA-coding sequence data: a case study of the Lecanoromycetes (Ascomycota).

The resolving power and statistical support provided by two protein-coding (RPB1 and RPB2) and three ribosomal RNA-coding (nucSSU, nucLSU, and mitSSU) genes individually and in various combinations were investigated based on maximum likelihood bootstrap analyses on lichen-forming fungi from the class Lecanoromycetes (Ascomycota). Our results indicate that the optimal loci (single and combined) to use for molecular systematics of lichen-forming Ascomycota are protein-coding genes (RPB1 and RPB2). RPB1 and RPB2 genes individually were phylogenetically more efficient than all two- and three-locus combinations of ribosomal loci. The 3rd codon position of each of these two loci provided the most characters in support of phylogenetic relationships within the Lecanoromycetes. Of the three ribosomal loci we used in this study, mitSSU contributed the most to phylogenetic analyses when combined with RPB1 and RPB2. Except for the mitSSU, ribosomal genes were the most difficult to recover because they often contain many introns, resulting in PCR bias toward numerous and intronless co-extracted contaminant fungi (mainly Dothideomycetes, Chaetothyriomycetes, and Sordariomycetes in the Ascomycota, and members of the Basidiomycota), which inhabit lichen thalli. Maximum likelihood analysis on the combined five-locus data set for 82 members of the Lecanoromycetes provided a well resolved and well supported tree compared to existing phylogenies. We confirmed the monophyly of three recognized subclasses in the Lecanoromycetes, the Acarosporomycetidae, Ostropomycetidae, and Lecanoromycetideae; the latter delimited as monophyletic for the first time, with the exclusion of the family Umbilicariaceae and Hypocenomyce scalaris. The genus Candelariella (formerly in the Candelariaceae, currently a member of the Lecanoraceae) represents the first evolutionary split within the Lecanoromycetes, before the divergence of the Acarosporomycetidae. This study provides a foundation necessary to guide the selection of loci for future multilocus phylogenetic studies on lichen-forming and allied ascomycetes.

Ascomycota↗
PubMed2004

Expression of CXCL16 in human rectal cancer.

Local immunoregulation mediated by infiltration of inflammatory cells into colorectal adenocarcinomas is important for tumour progression. Tumour-associated macrophages and T cells are predominant components of chemokine-guided infiltrate of most colorectal tumours. CXCL16 is a newly discovered CXC chemokine expressed by antigen presenting cells attracting Th1, Tc and NK T cells. In this study, which is the first report on expression of the chemokine CXCL16 in human rectal cancer, CXCL16 gene and protein expression were analysed in cancer and normal adjacent tissue. Immunohistochemistry revealed CXCL16 expression in macrophages in normal tissue. The CXCL16 was found to a very limited extent in tumour-associated macrophages. Western blot analysis showed a suppression of CXCL16 protein in rectal cancer compared to non-cancer tissue in 83% of the patients (n=23, P=0.003). However, with real-time PCR mRNA was not down-regulated in the cancer compared to normal tissue, which may depend on regulated factor(s) at the level of translation and/or post-translation. The results may reflect one of the immunological mechanisms underlying carcinogenesis.

Adenocarcinoma↗
PubMed1996

Prophylaxis in liver transplant recipients using a fixed dosing schedule of hepatitis B immunoglobulin.

Prophylactic hepatitis B immunoglobulin (HBIg) reduces the risk of reinfection in hepatitis B surface antigen (HBsAg)-positive liver transplant recipients. In the medical center of this study, high-dose HBIg immunoprophylaxis is administered at a fixed dose of 10,000 IU monthly, and in this study, the long-term efficacy of this treatment regimen was examined. Of 52 HBsAg-positive liver transplant recipients, 24 were administered HBIg immunoprophylaxis, and 28 were administered no specific therapy; the 2-year recurrence rates (defined by the reappearance of HBsAg) were 19% and 76%, respectively. Fifty-four percent of the HBIg-treated patients were positive for HBeAg or hepatitis B virus (HBV) DNA (by hybridization assay) pretransplantation. In patients administered monthly HBIg, intrapatient and interpatient variability in trough antibody to HBsAg (anti-HBs) titer was significant, highlighting the potential difficulties of using anti-HBs titer to guide therapy. Trough anti-HBs titers were less in patients who became HBsAg positive than in patients who remained HBsAg-negative (490 vs. 1290 mIU/mL) (P = .0001), reflecting either the cause or effect of HBV reinfection. Of 9 patients who remained HBsAg-negative and who were administered monthly HBIg for at least 1 year, HBV DNA by polymerase chain reaction amplification was detectable in the sera of 67%, the lymphocytes of 50%, and the liver of 57%. In conclusion, a fixed monthly dose of HBIg reduces the recurrence of HBs antigenemia, even in patients with indices of active viral replication pretransplantation. The presence of residual virus in the majority of patients administered HBIg suggests that long-term HBIg administration may be necessary.

Actuarial Analysis↗
PubMed2026

Teleost lincRNAs: Functional roles, regulatory mechanisms, and future applications in aquaculture.

Long intergenic non-coding RNAs (lincRNAs) regulate gene expression across vertebrate physiological systems, yet their functional roles in teleost fish remain incompletely synthesized. This review systematically integrates current evidence through PRISMA-guided searches across PubMed, Web of Science, and Scopus, identifying ten lincRNA-focused functional studies with genetic, mechanistic, or developmental validation, complemented by twenty two supplementary contextual references. Findings span development, immunity, environmental adaptation, reproduction, regeneration, and toxicology, with each association graded as experimentally validated, bioinformatically predicted, correlational, or speculative. This synthesis offers three core contributions. First, it shows that cis-acting regulation on neighboring genes, mediated through Wnt, NF-κB, and AHR signaling, is the dominant validated lincRNA mechanism across teleost physiological domains. Second, it demonstrates that direct experimental validation, primarily via CRISPR-Cas9 and chromatin-capture assays, remains concentrated in zebrafish, whereas aquaculture-species associations remain largely correlational. Third, it identifies two findings that challenge current lincRNA classification: unexpected regulatory directionality at the slincR-sox9b locus, and micropeptide-encoding potential within annotated lincRNAs. Together, these contributions establish an evidence-graded foundation for future mechanistic studies and translational aquaculture applications.

Aquaculture↗
PubMed2005

Joint Bayesian estimation of alignment and phylogeny.

We describe a novel model and algorithm for simultaneously estimating multiple molecular sequence alignments and the phylogenetic trees that relate the sequences. Unlike current techniques that base phylogeny estimates on a single estimate of the alignment, we take alignment uncertainty into account by considering all possible alignments. Furthermore, because the alignment and phylogeny are constructed simultaneously, a guide tree is not needed. This sidesteps the problem in which alignments created by progressive alignment are biased toward the guide tree used to generate them. Joint estimation also allows us to model rate variation between sites when estimating the alignment and to use the evidence in shared insertion/deletions (indels) to group sister taxa in the phylogeny. Our indel model makes use of affine gap penalties and considers indels of multiple letters. We make the simplifying assumption that the indel process is identical on all branches. As a result, the probability of a gap is independent of branch length. We use a Markov chain Monte Carlo (MCMC) method to sample from the posterior of the joint model, estimating the most probable alignment and tree and their support simultaneously. We describe a new MCMC transition kernel that improves our algorithm's mixing efficiency, allowing the MCMC chains to converge even when started from arbitrary alignments. Our software implementation can estimate alignment uncertainty and we describe a method for summarizing this uncertainty in a single plot.

Algorithms↗
PubMed2005

Polypropylenimine dendrimer-induced gene expression changes: the effect of complexation with DNA, dendrimer generation and cell type.

Polypropylenimine (PPI) dendrimers appear attractive non-viral vectors for the delivery of genes, antisense oligonucleotides, and small interfering RNA (siRNA). However, the effects of these synthetic gene delivery vectors on global gene expression are poorly understood. Here we have examined the toxicogenomics of generation 2 (DAB-8) and generation 3 (DAB-16) PPI dendrimers in two human cell lines. At concentrations and treatment protocols routinely used for gene and oligonucleotide transfection, PPI dendrimers alone elicited marked changes in endogenous gene expression in A431 epithelial cells. The extent of PPI-induced gene changes appeared to be dependent on the dendrimer generation as the number of genes affected was greater with G3 compared to G2 PPI dendrimers in A431 cells. The signature of DAB16-induced gene changes in A549 cells was different to those elicited in A431 cells implying a strong dependence on cell type. The DAB-16 polymer complexed with DNA (dendriplexes) also elicited marked gene expression changes in A549 cells but with a signature that was different from the polymer alone implying that dendriplexes are "recognised" by cells as chemical entities that are distinct from the polymer alone. Alterations in expression of a variety of gene ontologies were observed including those involved in defence responses, cell proliferation and apoptosis. Although there was a tendency for increased DNA damage in cells treated with DAB16 alone or its DNA dendriplexes as detected by the COMET assay, these differences were not statistically significant. These data show for the first time that PPI-dendrimers, separate from their capability as transfection reagents, can intrinsically alter the expression of many endogenous genes that could potentially lead to them exerting multiple biological effects in cells. The impact and consequences of polymer-induced gene changes should guide their rational use as delivery systems for gene-based therapeutics.

Cell Line↗
PubMed2004

Escherichia coli glutaminyl-tRNA synthetase is electrostatically optimized for binding of its cognate substrates.

Natural evolution has resulted in protein molecules displaying a wide range of binding properties that include extremes of affinity and specificity. A detailed understanding of the principles underlying protein structure-function relationships, particularly with respect to binding properties, would greatly enhance molecular engineering and ligand design studies. Here, we have analyzed the interactions of an aminoacyl-tRNA synthetase for which strong evolutionary pressure has enforced high specificity for substrate binding and catalysis. Electrostatic interactions have been identified as one efficient mechanism for enhancing binding specificity; as such, the effects of charged and polar groups were the focus of this study. The binding of glutaminyl-tRNA synthetase from Escherichia coli to several ligands, including the natural substrates, was analyzed. The electrostatic complementarity of the enzyme to its ligands was assessed using measures derived from affinity optimization theory. The results were independent of the details of the calculational parameters, including the value used for the protein dielectric constant. Glutamine and ATP, two of the natural ligands, were found to be extremely complementary to their binding sites, particularly in regions seen to make electrostatic interactions in the structure. These data suggest that the optimization of electrostatic interactions has played an important role in guiding the evolution of this enzyme. The results also show that the enzyme is able to effectively select for high affinity and specificity for the same chemical moieties both in the context of smaller substrates, and in that of a larger reactive intermediate. The regions of greatest non-complementarity between the enzyme and ligands are the portions of the ligand that make few polar contacts with the binding site, as well as the sites of chemical reaction, where overly strong electrostatic binding interactions with the substrate could hinder catalysis. The results also suggest that the negative charge on the phosphorus center of glutaminyl-adenylate plays an important role in the tight binding of this intermediate, and thus that adenylate analogs that preserve the negative charge in this region may bind substantially tighter than analogs where this group is replaced with a neutral group, such as the sulfamoyl family, which can make similar hydrogen bonds but is uncharged.

Adenosine Monophosphate↗
PubMed2000

Expression of ram-5 in the structural cell is required for sensory ray morphogenesis in Caenorhabditis elegans male tail.

Tissue morphogenesis requires complex cellular interaction and communication. The sensory ray in the Caenorhabditis elegans male tail has a simple cellular make-up and a non-essential function, thus providing an ideal model for studying the mechanisms guiding morphogenesis. We present here the analysis of a novel gene, ram-5, mutations of which are characterized by abnormal lumpy rays in the male tail. Microscopic analysis and behavioral studies revealed that lumpy rays contain operational sensory neurons. However, abnormalities were observed in the hypodermis and structural cells as well as in appositions between these two cell types. Molecular cloning and expression studies revealed that the ram-5 gene encodes a transmembrane protein localized in sensory ray support cells, the structural cells. Expression of ram-5 in these cells is required for normal ray morphogenesis. ram-5-dependent cell-cell communication is implicated in organizing the structural cell and the hypodermis, potentially through adhesion at the structural cell-hypodermal cell border.

Amino Acid Sequence↗
PubMed1998

Report of the NIH Panel To Define Principles of Therapy of HIV Infection.

Recent research advances have afforded substantially improved understanding of the biology of HIV infection and the pathogenesis of AIDS. With the advent of sensitive tools for monitoring HIV replication in infected persons, the risk for disease progression and death can be assessed accurately and the efficacy of anti-HIV therapies can be determined directly. Furthermore, when used appropriately, combinations of newly available, potent antiviral therapies can effect prolonged suppression of detectable levels of HIV replication and circumvent the inherent tendency of HIV to generate drug-resistant viral variants. However, as antiretroviral therapy for HIV infection has become increasingly effective, it has also become increasingly complex. Familiarity with recent research advances is needed to ensure that newly available therapies are used in ways that most effectively improve the health and prolong the lives of HIV-infected persons. To enable practitioners and HIV-infected persons to best use rapidly accumulating new information about HIV disease pathogenesis and treatment, the Office of AIDS Research of the National Institutes of Health (NIH) sponsored the NIH Panel To Define Principles of Therapy of HIV Infection. This Panel was asked to define essential scientific principles that should be used to guide the most effective use of antiretroviral therapies and viral load testing in clinical practice. On the basis of detailed consideration of the most current data, the Panel delineated 11 principles that address issues of fundamental importance for the treatment of HIV infection. These principles provide the scientific basis for the specific treatment recommendations made by the Panel on Clinical Practices for the Treatment of HIV Infection sponsored by the Department of Health and Human Services and the Henry J. Kaiser Family Foundation. The reports of both of these panels are provided in this supplement. Together, they summarize new data and provide both the scientific basis and specific guidelines for the treatment of HIV-infected persons. This information will be of interest to health care providers, HIV-infected persons, HIV and AIDS educators, public health educators, public health authorities, and all organizations that fund medical care of HIV-infected persons.

Anti-HIV Agents↗
PubMed2001

Signal transduction in neuronal migration: roles of GTPase activating proteins and the small GTPase Cdc42 in the Slit-Robo pathway.

The Slit protein guides neuronal and leukocyte migration through the transmembrane receptor Roundabout (Robo). We report here that the intracellular domain of Robo interacts with a novel family of Rho GTPase activating proteins (GAPs). Two of the Slit-Robo GAPs (srGAPs) are expressed in regions responsive to Slit. Slit increased srGAP1-Robo1 interaction and inactivated Cdc42. A dominant negative srGAP1 blocked Slit inactivation of Cdc42 and Slit repulsion of migratory cells from the anterior subventricular zone (SVZa) of the forebrain. A constitutively active Cdc42 blocked the repulsive effect of Slit. These results have demonstrated important roles for GAPs and Cdc42 in neuronal migration. We propose a signal transduction pathway from the extracellular guidance cue to intracellular actin polymerization.

Actins↗
PubMed2001

Position within the host intron is critical for efficient processing of box C/D snoRNAs in mammalian cells.

In mammalian cells, all small nucleolar RNAs (snoRNAs) that guide rRNA modification are encoded within the introns of host genes. A database analysis of human box C/D snoRNAs revealed conservation of their intronic location, with a preference for 70-80 nt upstream of the 3' splice site. Transfection experiments showed that synthesis of gas5-encoded U75 and U76 snoRNAs dropped significantly for mutant constructs possessing longer or shorter spacers between the snoRNA and the 3' splice site. However, the position of the snoRNA did not affect splicing of the host intron. Substitution mutations within the spacer indicated that the length, but not the specific sequence, is important. A in vitro system that couples pre-mRNA splicing and processing of U75 has been developed. U75 synthesis in vitro depends on its box C and D sequences and requires an appropriate spacer length. Further mutational analyses both in vivo and in vitro, with subsequent mapping of the branch points, revealed that the critical distance is from the snoRNA coding region to the branch point, suggesting synergy between splicing and snoRNA release.

Animals↗
PubMed1993

Dominant lethality by expression of a catalytically inactive class I tRNA synthetase.

Alignment-guided mutagenesis was used to create an inactive, but toxic, aminoacyl-tRNA synthetase. An Asp-96-->Ala (D96A) replacement in the nucleotide binding fold of the class I Escherichia coli isoleucyl-tRNA synthetase inactivates the enzyme without disrupting its competence for binding isoleucine tRNA. Expression of plasmid-encoded mutant enzyme in a cell with a wild-type ileS chromosomal allele resulted in cell death. Introduction of a second K732T substitution previously shown to weaken tRNA binding gives an inactive D96A/K732T double mutant. Expression of the double mutant is not lethal to E. coli. D96A but not the double mutant significantly inhibited in vitro charging of isoleucine tRNA by the wild-type enzyme. The results suggest a dominant tRNA binding-dependent arrest of cell growth caused by a reduction in the pool of a specific tRNA. Specific tRNA binding drugs may have therapeutic applications for treatment of microbial pathogens.

Amino Acid Sequence↗
PubMedDate not supplied

Predictors of virologic response to ritonavir-boosted protease inhibitors.

The primary mechanism of resistance to protease inhibitors involves the stepwise accumulation of mutations that alter and block the substrate binding site of HIV protease. The large degree of cross-resistance among the different protease inhibitors is a source of considerable concern for the management of patients after treatment failure. Although the output of HIV-resistance tests has been based on therapeutically arbitrary criteria, there is now an ongoing move towards correlating test interpretation with virologic outcomes on treatment. This approach is undeniably superior, in principle, for tests intended to guide drug choices. However, the predictive accuracy of a given stratagem that links genotype or phenotype to drug response is strongly influenced by the study design, data capture and the analytical methodology used to derive it. There is no definitively superior methodology for generating a genotype-response association for use in interpreting a resistance test, and the various approaches used to date all have their strengths and weaknesses. Combining the information of therapeutic drug monitoring and resistance tests is likely to be of greatest clinical utility in antiretroviral-experienced patients harboring HIV strains with reduced susceptibility. The combination of pharmacologic and virologic parameters as a predictor of the virologic response has been merged into the parameter known as "inhibitory quotient". This article discusses the potential interest of the use of inhibitory quotients as an approach for enhancing the potency and durability of boosted protease inhibitors against protease inhibitor-resistant viruses.

Anti-HIV Agents↗
PubMed2004

Triiodothyronine (T3) and 1,25-dihydroxyvitamin D3 (1,25D3) inversely regulate OPG gene expression in dependence of the osteoblastic phenotype.

Both thyroid hormones and 1,25-dihydroxyvitamin D3 (1,25D3) are essential for normal development and maintenance of the skeleton. They regulate osteoblastic differentiation by influencing expression of osteoblast specific genes like osteocalcin (OCN). Mice deficient in OCN, the most abundant noncollagenous protein of the bone matrix, develop a phenotype characterized by higher bone mass and bone of improved quality. Osteoprotegerin (OPG), another protein important for bone metabolism, protects bone and is a regulator of the osteoclast development. 1,25D3 down regulates the basal expression of these two proteins in osteoblasts and osteoblast-like cells. The involvement of these hormones and proteins in the bone metabolism guided us to compare their regulation in cell lines with different osteoblastic phenotypes. We found that T3 increased OCN mRNA levels in MC3T3-E1 osteoblastic cells independent from their phenotype albeit with different potency but not in the bone marrow-derived stromal cell line ST2. OPG mRNA expression levels were only stimulated by T3 in mature MC3T3-E1 cells, which have the capacity to mineralize, but not in pre-osteoblastic MC3T3-E1 cells or in ST2 cells. In the mineralizing osteoblastic cells 1,25D3 inhibited T3-induced expression for OPG mRNA but not OCN mRNA. In the pre-osteoblastic cell line with undetectable OPG mRNA levels, either basal or T3-stimulated, 1,25D3 inhibited OCN mRNA expression completely. Our results emphasize the importance of balanced regulation of mRNA transcript levels for OPG and OCN, by both hormones and probably other systemic factors to enable a fine-tuning of bone metabolism at specific skeletal sites.

3T3 Cells↗
PubMed2003

Eugenol suppresses cyclooxygenase-2 expression in lipopolysaccharide-stimulated mouse macrophage RAW264.7 cells.

Inducible cyclooxygenase (COX-2) has been implicated in the processes of inflammation and carcinogenesis. Thus, the potential COX-2 inhibitors have been considered as anti-inflammatory or cancer chemopreventive agents. In this study, the methanolic extract of the cortex of Eugenia caryophyllata Thunberg (Myrtaceae) was found to potently inhibit the prostaglandin E(2) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.7 cells (98.3% inhibition at the test concentration of 10 microg/ml). Further, hexane-soluble layer was the most active partition compared to ethyl acetate, n-butanol, and water-soluble parts. By bioassay-guided fractionation of hexane-soluble partition, eugenol was isolated and exhibited a significant inhibition of PGE(2) production (IC(50) = 0.37 microM). In addition, eugenol suppressed the cyclooxygenase-2 (COX-2) gene expression in LPS-stimulated mouse macrophage cells. On the line of COX-2 playing an important role in colon carcinogenesis further study was designed to investigate the effect of eugenol on the growth and COX-2 expression in HT-29 human colon cancer cells. Eugenol inhibited the proliferation of HT-29 cells and the mRNA expression of COX-2, but not COX-1. This result suggests that eugenol might be a plausible lead candidate for further developing the COX-2 inhibitor as an anti-inflammatory or cancer chemopreventive agent.

Animals↗
PubMed2004

Identification of 20 microRNAs from Oryza sativa.

MicroRNAs (miRNAs) are present in both plant and animal kingdoms and represents a growing family of non-coding RNAs. These tiny RNAs act as small guides and direct negative regulations usually in the process of development through sequence complementarity to target mRNAs. Although a large number of miRNAs have been identified from various animals, so far plant miRNA studies have focused mainly on Arabidopsis. Here we describe the identification of 20 miRNAs from a rice cDNA library. All the miRNAs were presumably processed from precursors with stem-loop structures and were positively detected in rice cells from at least one tissue, some of which showed tissue-specific expression. Twenty-three unique rice genes were identified to be feasible targets for seven rice miRNAs, including four members of Scarecrow-like transcription factor, the targets of miR-39 that had been characterized in Arabidopsis. Lacking long complementarity, the regulatory targets of 13 miRNAs remain to be further investigated. A possible mechanism of translational repressor for plant miRNAs that lack perfect complementarity to target mRNAs is discussed.

Base Sequence↗
PubMed2001

Cloning and characterization of Arabidopsis thaliana AtNAP57--a homologue of yeast pseudouridine synthase Cbf5p.

Rat Nap57 and its yeast homologue Cbf5p are pseudouridine synthases involved in rRNA biogenesis, localized in the nucleolus. These proteins, together with H/ACA class of snoRNAs compose snoRNP particles, in which snoRNA guides the synthase to direct site-specific pseudouridylation of rRNA. In this paper we present an Arabidopsis thaliana protein that is highly homologous to Cbf5p (72% identity and 85% homology) and NAP57 (67% identity and 81% homology). Moreover, the plant protein has conserved structural motifs that are characteristic features of pseudouridine synthases of the TruB class. We have named the cloned and characterized protein AtNAP57 (Arabidopsis thaliana homologue of NAP57). AtNAP57 is a 565 amino-acid protein and its calculated molecular mass is 63 kDa. The protein is encoded by a single copy gene located on chromosome 3 of the A. thaliana genome. Interestingly, the AtNAP57 gene does not contain any introns. Mutations in the human DKC1 gene encoding dyskerin (human homologue of yeast Cbf5p and rat NAP57) cause dyskeratosis congenita a rare inherited bone marrow failure syndrome characterized by abnormal skin pigmentation, nail dystrophy and mucosal leukoplakia.

Amino Acid Sequence↗
PubMed2006

Androgen and estrogen receptor-beta distribution within spinal-projecting and neurosecretory neurons in the paraventricular nucleus of the male rat.

Activation of the hypothalamic-pituitary-adrenal (HPA) axis is initiated by neurosecretory neurons residing within the medial parvicellular part of the hypothalamic paraventricular nucleus (PVN). Despite the potency by which sex steroids operate on HPA and medial parvocellular responses to stress, previous topographic and phenotypic studies suggest that gonadal steroid hormone receptors are scarcely, if at all, expressed by PVN neurons controlling anterior pituitary corticotropes. Guided by the pattern of retrograde accumulation of fluorogold, we used a direct connectional approach to define the distribution of androgen receptors (AR) and estrogen-beta receptors (ER-beta) within populations of neurosecretory vs. nonneurosecretory neurons in the PVN. Juxtaposition of AR-immunoreactivity (ir) and ER-beta mRNA to the pattern of intravenous fluorogold labeling showed these steroid hormone receptors to be concentrated within portions of the PVN devoid of neurosecretory neurons. Superimposing receptor profiles onto the pattern of spinal retrograde labeling confirmed a selective distribution of AR-ir within autonomic-related cells of the medial parvocellular division, including its dorsal, lateral, and ventral medial components. ER-beta mRNA expression was likewise concentrated within regions accumulating spinal tracer, highest within the ventral aspect of the PVN. These results indicate a direct influence of gonadal hormones on preautonomic effector neurons and remain in keeping with an indirect influence of androgens on adrenocorticotropin-regulating neurons in the PVN.

Androgens↗