Circadian PER2 protein oscillations do not persist in cycloheximide-treated mouse embryonic fibroblasts in culture

It is not known whether the endogenous mammalian core clock proteins sustain measurable oscillations in cells in culture where de novo translation is pharmacologically inhibited. We studied here the mammalian core clock protein PER2, which undergoes robust circadian oscillations in both abundance and phosphorylation. With a newly developed antibody that enables tracing the endogenous PER2 protein oscillations over circadian cycles with cultured mouse embryonic fibroblast cells, we provide evidence that PER2 does not persist noticeable circadian rhythms when translation is inhibited.     

Multi-male group and bidirectional sex change in the gobiid fish, <Emphasis Type="Italic">Trimma caudomaculatum</Emphasis>

The gobiid fish, Trimma caudomaculatum, lives in groups. We investigated group structure, mating system and bidirectional sex change of this species. Four groups examined contained more than two males. The males were significantly larger than the females. By the observations in aquarium, the males occupied a nest and the females visited the nest for spawning. While there was no specific pair bond, the males mated with multiple females. Hence, this species establishes multi-male groups. In the experiments, four larger females had changed sex to male among 25 females. The smallest male changed to female in the group of four males.     

Rmg8 and Rmg7, wheat genes for resistance to the wheat blast fungus,recognize the same avirulence gene AVR‐Rmg8

Rmg8 and Rmg7 are genes for resistance to the wheat blast fungus (Pyricularia oryzae), located on chromosome 2B in hexaploid wheat and chromosome 2A in tetraploid wheat, respectively. AVR‐Rmg8, an avirulence gene corresponding to Rmg8, was isolated from a wheat blast isolate through a map‐based strategy. The cloned fragment encoded a small protein containing a putative signal peptide. AVR‐Rmg8 was recognized not only by Rmg8, but also by Rmg7, suggesting that these two resistance genes are equivalent to a single gene from the viewpoint of resistance breeding.     

winged eye Induces Transdetermination of Drosophila Imaginal Disc by Acting in Concert with a Histone Methyltransferase,Su(var)3-9

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Toll‐like receptors 2 and 3 enhance melanogenesis and melanosome transport in human melanocytes

Because little is known about how the innate immune response influences skin pigmentation, we examined whether Toll‐like receptor (TLR) agonists participate in melanogenesis and melanosome transportation. We observed that TLR2/2 agonist HKLM and TLR3 agonist Poly(I:C) increased the amount of extracellular melanin from primary human epidermal melanocytes. HKLM, but not Poly(I:C), increased the melanogenic genes such as tyrosinase and dopachrome tautomerase. Poly(I:C) increased the expression of Rab27A, a molecule that facilitates melanosome transport to perimembranous actin filament. UVB irradiation induced Rab27A and melanosome transportation in a similar manner of Poly(I:C). SiRNA for TLR3 or Rab27A suppressed the perimembranous accumulation of Gp100‐positive vesicles in melanocytes and decreased melanin transfer to neighboring keratinocytes induced by both Poly(I:C) and UVB. These results suggest that the microenvironment in the epidermis and innate immune stimuli, such as microbiome and ultraviolet represented here by TLR2 and TLR3 agonists, could affect the melanogenesis in human melanocytes.     

Direct In Vivo Reprogramming with Sendai Virus Vectors Improves Cardiac Function after Myocardial Infarction

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Differential expression of a fructose receptor gene in honey bee workers according to age and behavioral role

Honey bee (Apis mellifera) workers contribute to the maintenance of colonies in various ways. The primary functions of workers are divided into two types depending on age: young workers (nurses) primarily engage in such behaviors as cleaning and food handling within the hive, whereas older workers (foragers) acquire floral nutrients beyond the colony. Concomitant with this age‐dependent change in activity, physiological changes occur in the tissues and organs of workers. Nurses supply younger larvae with honey containing high levels of glucose and supply older larvae with honey containing high levels of fructose. Given that nurses must determine both the concentration and type of sugar used in honey, gustatory receptors (Gr) expressed in the chemosensory organs likely play a role in distinguishing between sugars. Glucose is recognized by Gr1 in honey bees (AmGr1); however, it remains unclear which Gr are responsible for fructose recognition. This study aimed to identify fructose receptors in honey bees and reported that AmGr3, when transiently expressed in Xenopus oocytes, responded only to fructose, and to no other sugars. We analyzed expression levels of AmGr3 to identify which tissues and organs of workers are involved in fructose recognition and determined that expression of AmGr3 was particularly high in the antennae and legs of nurses. Our results suggest that nurses use their antennae and legs to recognize fructose, and that AmGr3 functions as an accurate nutrient sensor used to maintain food quality in honey bee hives.     

Novel glycoproteins inhibiting the binding of colorectal cancer cells to E-selectin

Novel glycoproteins carrying sialyl-LeA (SLeA) antigens (SL-GP) were isolated from ascites fluid from a patient with colorectal cancer by immunoaffinity chromatography. Their characteristics, including binding capacity to E-selectin, were investigated. SL-GP showed a typical mucin type amino acid composition in which Ser, Thr and Pro together accounted for greater than 50% of the total amino acid residues. A large amount of carbohydrate (about 80%) was present in SL-GP. The number of O-glycans carrying SLeA antigens comprised about 9% of the total number of O-glycosidic chains. SL-GP could bind to IL-1 treated HUVEC, and the binding was inhibited by anti-E-selectin and anti-SLeA monoclonal antibodies. The binding of colorectal cancer cells, LS 180, to HUVEC was assayed in the presence of SL-GP, oligosaccharides prepared from SL-GP and human milk SLeA hexasaccharide. SL-GP inhibited the binding most effectively, whereas equivalent amounts of the SL-GP oligosaccharides and milk SLeA hexasaccharide inhibited it only slightly. These results constitute direct evidence that a unique arrangement of SLeA antigens on the polypeptide chain, probably a cluster, is essential for the binding to E-selectin.