Galanin in adrenocorticotropic hormone cells is decreased by castration

Galanin (GAL) is a neuropeptide that is widely expressed in neuroendocrine tissues, including the adenohypophysis. Since GAL is expressed at higher levels in females, little attention has been paid to the regulation of GAL secretion in males. Here, we show that testosterone regulates GAL secretion in the adenohypophysis of male rats. Using double immunoelectron microscopy, we demonstrate that GAL cells possess three types of secretory granule: those with colocalization of GAL and adrenocorticotropic hormone (ACTH), those with GAL only, and those with ACTH only. The predominant granule type was that containing both GAL and ACTH, suggesting that GAL and ACTH are secreted at the same time. Indeed, adrenalectomy induced an acute decrease in the number of both GAL cells and ACTH cells. In contrast, castration resulted in a decrease in the proportion of GAL cells, while the proportion of ACTH cells remained unchanged. In addition, ACTH-strongly positive and GAL-positive cells were decreased while ACTH-weakly positive and GAL-negative cells were increased after castration. Testosterone treatment of castrated animals resulted in restoration of these levels to those of intact and sham operated animals. These results indicated that testosterone regulates GAL secretion in male animals.     

A new bisabolane-type sesquiterpenoid from Curcuma domestica

Biochemical Systematics and Ecology, Volume x, Issue x, Pages x–x (dd mm yyyy). A new bisabolane-type sesquiterpenoid from Curcuma domestica. Takahiro Ishii, Hiroshi Matsuura, Kunimitsu Kaya, Charles Santhanaraju Vairappan.

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Highlights? Chemical constituents of lowland and highland Curcuma domestica of Borneo are reported. ? Three sesquiterpenes and three curcuminoids secondary metabolites were found in common. ? Highland populations contained two additional bisabolane-type sesquiterpenoid metabolites. ? Curcuma domestica is reported as a new source for novel compound, bisacurol B.     

Transgene number-dependent, gene expression rate-independent rejection of Dd -, Kd-, or Dd Kd -transgened mouse skin or tumor cells from C57BL/6 Db Kb mice

Recipient cells migrating into the transplantation site of an allograft recognize histocompatibility antigens on the grafts and are cytotoxic against the grafts. Although the alloreactive immune response is predominantly directed at the major histocompatibility complex (major histocompatibility complex [MHC]; H-2 in mice) class I molecules, the basic mechanisms of allograft rejection (e.g., ligand-receptor interaction) remain unclear, because of the polymorphism and complexity of the MHC. To examine the role of MHC class I molecules in allograft rejection, D(d) , K(d) or D(d) K(d) -transgenic skin or tumor cells we established on a C57BL/6 (D(b) K(b) ) background and transplanted into C57BL/6 mice. Skin grafts from allogeneic (i.e., BALB/c, B10.D2, and BDF1) strains of mice were rejected from C57BL/6 mice on days 12-14 after grafting, whereas isografts were tolerated by these mice. Unexpectedly, skin grafts from D(d) -, K(d) -, and D(d) K(d) -transgenic C57BL/6 mice were rejected on days 12-14 in a transgene expression rate-independent manner from 9/19 (47%), 20/39 (51%), and 12/17 (71%) of C57BL/6 mice, respectively. Similarly, intradermally transplanted allogeneic (i.e., Meth A), but not syngeneic (i.e., EL-4), tumor cells were rejected from C57BL/6 mice; the growth of D(d) - or K(d) -transfected EL-4 cells was delayed by 10-13 days; and 4/10 (40%) of D(d) K(d) -transfected tumor cells were rejected from C57BL/6 mice. These results indicate that D(d) and K(d) genes are equivalent as allogeneic MHC class I genes and that C57BL/6 (D(b) K(b) ) mice reject D(d) -, K(d) -, or D(d) K(d) -transgened skin or tumor cells in a transgene number-dependent, gene expression rate-independent manner.     

A multifaceted genomics approach allows the isolation of the rice Pia-blast resistance gene consisting of two adjacent NBS-LRR protein genes

The Oryza sativa (rice) resistance gene Pia confers resistance to the blast fungus Magnaporthe oryzae carrying the AVR-Pia avirulence gene. To clone Pia, we employed a multifaceted genomics approach. First, we selected 12 R-gene analog (RGA) genes encoding nucleotide binding site-leucine rich repeats (NBS-LRRs) proteins from a region on chromosome 11 that shows linkage to Pia. By using seven rice accessions, we examined the association between Pia phenotypes and DNA polymorphisms in the 10 genes, which revealed three genes (Os11gRGA3-Os11gRGA5) exhibiting a perfect association with the Pia phenotypes. We also screened ethyl methane sulfonate (EMS)-treated mutant lines of the rice cultivar 'Sasanishiki' harboring Pia, and isolated two mutants that lost the Pia phenotype. DNA sequencing of Os11gRGA3-Os11gRGA5 from the two mutant lines identified independent mutations of major effects in Os11gRGA4. The wild-type 'Sasanishiki' allele of Os11gRGA4 (SasRGA4) complemented Pia function in both mutants, suggesting that SasRGA4 is necessary for Pia function. However, when the rice cultivar 'Himenomochi' lacking Pia was transfected with SasRGA4, the Pia phenotype was not recovered. An additional complementation study revealed that the two NBS-LRR-type R genes, SasRGA4 and SasRGA5, that are located next to each other and oriented in the opposite direction are necessary for Pia function. A population genetics analysis of SasRGA4 and SasRGA5 suggests that the two genes are under long-term balancing selection.     

Potential of D-erythro-C14-Sphingosine as an adjuvant for a fungal pesticide of Nomuraea rileyi

D-erythro-C(14)-Sphingosin (C(14)-Sph) was isolated as the germination accelerating factor in Nomuraea rileyi in our previous study. This activity was expected to support fungal infection by reduction of the infection time between conidial adhesion and invasion into the insect. In this study, we estimated the effect of C(14)-Sph with regard to the infection time. Conidia activated by C(14)-Sph shortened the time to about half, indicating the potential of C(14)-Sph as an adjuvant for fungal pesticide of N. rileyi.     

Development of a novel PPARγ ligand screening system using pinpoint fluorescence-probed protein

The activation of peroxisome-proliferator-activated receptor-γ (PPARγ), which plays a central role in adipocyte differentiation, depends on ligand-dependent co-activator recruitment. In this study, we developed a novel method of PPARγ ligand screening by measuring the increase in fluorescent polarization accompanied by the interaction of a fluorescent co-activator and PPARγ. Sterol receptor co-activator-1 (SRC-1), a major PPARγ co-activator, was probed by fluorescent TAMRA by the Amber codon fluorescence probe method. Polarization was increased by adding PPARγ ligands to a solution containing labeled SRC-1 (designated TAMRA-SRC-S) and PPARγ. The disassociation constants (Kd) of the PPARγ synthesized ligands, pioglitazone (221 nM), troglitazone (83.0 nM), and 15-deoxy-Δ12,14-prostaglandin J(2) (15d-ΔPGJ(2)) (156 nM), were determined by this method. Farnesol (2.89 μM) and bixin (21.1 μM), which we have reported to be PPARγ ligands, increased the fluorescent polarization. Their Kd values were in agreement with the ED(50) values obtained in the luciferase assay. The results indicate that the method is valuable for screening natural PPARγ ligands.     

The effect of amino acids on the C₁₄-sphingosine-triggered germination of Nomuraea rileyi, and surface amino acids on Spodoptera litura fabricius

D-erythro-C??-Sphingosine (C??-Sph) accelerated the germination of Nomuraea rileyi in a solution containing peptone, but activity declined to a large degree in water. This suggests the presence of a co-factor in C??-Sph-triggered germination. Since the main role of peptone is to supply nitrogen constituents, we examined the effects of various nitrogen constituents. It was found that Ala and His were highly effective for C??-Sph-triggered germination.     

Aspartyl aminopeptidase is imported from the cytoplasm to the vacuole by selective autophagy in Saccharomyces cerevisiae

Macroautophagy is a catabolic process by which cytosolic components are sequestered by double membrane vesicles called autophagosomes and sorted to the lysosomes/vacuoles to be degraded. Saccharomyces cerevisiae has adapted this mechanism for constitutive transport of the specific vacuolar hydrolases aminopeptidase I (Ape1) and α-mannosidase (Ams1); this process is called the cytoplasm to vacuole targeting (Cvt) pathway. The precursor form of Ape1 self-assembles into an aggregate-like structure in the cytosol that is then recognized by Atg19 in a propeptide-dependent manner. The interaction between Atg19 and autophagosome-forming machineries allows selective packaging of the Ape1-Atg19 complex by the autophagosome-like Cvt vesicle. Ams1 also forms oligomers and utilizes the Ape1 transport system by interacting with Atg19. Although the mechanism of selective transport of the Cvt cargoes has been well studied, it is unclear whether proteins other than Ape1 and Ams1 are transported via the Cvt pathway. We describe here that aspartyl aminopeptidase (Yhr113w/Ape4) is the third Cvt cargo, which is similar in primary structure and subunit organization to Ape1. Ape4 has no propeptide, and it does not self-assemble into aggregates. However, it binds to Atg19 in a site distinct from the Ape1- and Ams1-binding sites, allowing it to "piggyback" on the Ape1 transport system. In growing conditions, a small portion of Ape4 localizes in the vacuole, but its vacuolar transport is accelerated by nutrient starvation, and it stably resides in the vacuole lumen. We propose that the cytosolic Ape4 is redistributed to the vacuole when yeast cells need more active vacuolar degradation.