The pattern of uterine innervation by noradrenergic (NA) and acetylcholinesterase-positive (AChE) nerves in different reproductive stages of the adult Japanese long-fingered bats were investigated histochemically and immunohistochemically. In the non-pregnant bat, the uterine horn was supplied with abundant NA and AChE nerves. These two types of nerves were closely associated with the uterine arteries and myometrial smooth muscles. In the pregnant bat, NA and AChE nerves supplying the uterus did not degenerate much during hibernating period, but reduced markedly after arousal. In the postpartum bat, the density of nerves recovered progressively. The significant change in the innervation pattern of uterine NA and AChE nerves in the pregnant bats under and after hibernation, and in the postpartum bat must be considered in relation to the adrenergic and cholinergic controlling mechanisms on the uterine function that is matched for the unique reproductive cycle of this bat.

In sexually mature Bengalese finches, acoustic structures of distance calls show sexual difference. The dorsomedial nucleus (DM) of intercollicular complex is known as the midbrain vocal center of distance calls. Neural input from the robust nucleus of archistriatum (RA) was observed in the DM of sexually mature males, but not observed in that of sexually mature females. The purpose of this study is to clarify some more details of physiological function of the neural system in the DM in distance call production. Electrical stimulation to the DM of both sexes induced a call acoustically similar to distance calls, whose duration depended on the number of the pulses/train of electrical stimulation; electrical stimulation in relatively large (or small) numbers of pulses/train induced calls with relatively long (or short) duration, respectively. Multi-unit spikes were recorded from neurons in the DM. The increment of the frequency of recorded spikes was large when the bird vocalized distance calls, and the number of the frequency decreased when the bird vocalized calls whose duration was shorter than that of distance calls. These results suggest that the neural system in the DM controls duration of distance calls in sexually mature males and females. Electrical stimulation to the DM under different pulse frequencies induced calls with different patterns of time-frequency characteristics. The relation between the pulse frequencies and time-frequency characteristics showed sexual difference. The relation between them in RA-lesioned males was similar to that in females. These results suggest that the neural circuit in the DM of sexually mature males is consisted of sexually common neural circuit controlled by the neural input from the RA, and that these sexually different neural system produce sexually different acoustic structures of distance calls.

The rearing condition necessary for behavioral compensation after sensory deprivation was investigated in the cricket Gryllus bimaculatus. The right-cercus-ablated cricket was reared in a glass vial with a slightly larger diameter than the body length of the cricket. After two weeks of rearing in the vial, the air-puff-evoked escape behavior of the cricket was investigated. The response rate (relative occurrence of the escape behavior after a standard air puff) obtained was identical with that of crickets reared in a large cage. On the other hand, unlike crickets reared in a large cage, the distorted escape directional property of the cricket reared in the vial was not compensated at all. Control experiments proved that the restraint in the vial did not affect the motor system, and the air motion from environments was not essential for the compensational recovery of the escape direction. Therefore, the ablated crickets required spontaneous walking in order to compensate the directionality of their escape. A self-generated wind caused by spontaneous walking appears necessary for the crickets to realize the defect of their sensory system and to compensate the related escape behavior. A hypothesis for the compensation mechanism based on the efference copy signal is proposed.

The b locus is one of the most familiar pigmentation loci in the medaka, but its biochemical function is still unknown. Here we report induction of new mutations at the b locus by radiation and ENU. We also characterized all these mutations and previously isolated spontaneous ones on the phenotypic basis. Unexpectively, all the 18 induced mutations reduced melanin contents in both eyes and skin correlatively, although degree of reduction was varied from mutations to mutations. Moreover, presumed null mutants (b^s8, b^g8, b^c2, b^d3, b^d6, b^g13, b^g19, b^g24) had slightly melanized (dark red) eyes. These results suggest that the b-locus product plays an important but not a critical role in melanogenesis. The spontaneous mutants were divided into two types: one (b^dl2, b^dl3, and b^p) had similarities with the induced mutants in that they had slightly colored eyes and skin, the other (b^v, B′, b^d, b^dl1, and b) exhibited normally black eyes but lightly colored skin. The present study supports our recent results (Fukamachi et al., 2001) that mutational changes were found in the coding region of the b gene in some of the mutants which reduced both eyes and skin melanogenesis, while the mutational change for the b allele could not be found there. We speculate that the b^v, B′, b^d, b^dl1, and b alleles might arise by the mutations in the regulatory region for skin melanogenesis.

Sea urchins of the genus Echinometra are abundant on Okinawa reef flats in southern Japan. The Okinawan Echinometra is designated into four sympatric and closely related species: A, B, C, and D (Ea, Eb, Ec, and Ed). The sperm head size and shape gradually changes to become longer and more slender according to the following order: Ea, Eb, Ec, and Ed. To obtain information regarding speciation in Okinawan Echinometra, this study examined comparatively the energy production system of spermatozoa of Ea, Eb, Ec, and Ed. All spermatozoa contained cholesterol and several kinds of phospholipids. Glycogen, glucose, and triglyceride were present at extremely low levels. After incubation in sea-water, a decrease in the level of phosphatidylcholine (PC) was observed in all spermatozoa concomitantly with activation of motility and respiration. The hydrolysis of PC correlated with the activity of phospholipase A₂. Interestingly, the amount of PC consumed, the respiratory rate, and the phospholipase A₂ activity in spermatozoa of Ea and Eb were approximately two-fold higher than those of Ec and Ed. Ultrastructural studies showed that lipid bodies within mitochondria were present in the midpieces of all species of spermatozoa. They became small or disappeared after incubation in seawater. Thus, the results obtained strongly suggest that spermatozoa of Ea, Eb, Ec, and Ed all use PC located in the lipid bodies as a substrate for energy metabolism. Also, it seems likely that energy production activities in Ea and Eb spermatozoa are stronger than those in Ec and Ed. The properties of energy metabolism in different species of sea urchin may be related to their habitat.

A 340 bp DNA fragment was amplified from barnacle (Megabalanus volcano) cDNA by polymerase chain reaction using primers designed based on the amino acid sequences of barnacle cadmiuminducible peptides CdIP1 and CdIP2. The whole sequence was determined by rapid amplification of cDNA ends method. The cDNA contained an open reading frame encoding 71 amino acid residues and the sequences for CdIP1 and CdIP2 were found to be located in the center of this coding region. Although CdIP1 and CdIP2 had been detected only in the cadmium-exposed barnacles, their mRNA was present both in cadmium-exposed barnacles and in unexposed barnacles. These results suggest that posttranslational proteolytic processing may be induced in the presence of cadmium.

Acrosome reaction-inducing substance (ARIS) in the jelly coat of starfish eggs is a highly sulfated proteoglycan-like molecule of an apparent molecular size over 10⁴kDa and plays a pivotal role in the induction of acrosome reaction in homologous spermatozoa. It is known in Asterias amurensis that ARIS binds to a restricted area of the anterior portion of sperm head, and that a glycan fragment of ARIS, named Fragment 1, consisting of 10 repeats or so of a pentasaccharide unit retains the biological activity of ARIS to an appreciable extent. In this report, we have shown the binding of Fragment 1, a relatively small pure glycan fragment of ARIS, to the putative ARIS receptor on the sperm surface by three independent methods. First, the specific binding of P-ARIS to isolated sperm membranes was monitored in real-time by using a surface plasmon resonance detector, namely a Biacore sensor system. The specific and quantitative binding of Fragment 1 to the intact sperm and to isolated sperm membranes was similarly monitored. Secondly, the binding of ¹²⁵I-labeled Fragment 1 to the intact sperm was stoichiometrically measured, for which we had developed a unique procedure for radioiodination of saccharide chains. It is found that Fragment 1 competes with P-ARIS for the binding to ARIS-receptor, suggesting that Fragment 1 is a useful ligand in the search for ARIS receptor protein(s). Thirdly, the putative receptor molecules were specifically labeled by using Fragment 1 as a ligand for photoaffinity crosslink technique. Taking these results into account, we conclude that starfish sperm have the ARIS receptor, which consists most probably of 50 to 60 kDa proteins, of reasonably high affinity (for Fragment 1, K_d=15 μM, B_max=8.4×10⁴ per cell).

We have previously performed suppression subtractive hybridization to identify genes that were induced during prolactin (PRL)-driven lobuloalveolar development of the mammary gland. This suggested that cortactin-binding protein 90 (CBP90), which is known to be a brain-specific protein that binds to cortactin, was expressed under the regulation of PRL in the mammary glands (preliminary observation). In this study, the expression of CBP90 was examined in the mammary glands of mice under manipulated hormonal circumstances. PRL treatment by 9 days of pituitary grafting induced CBP90 expression in the normal mammary glands but not in the cleared fat pads, while cortactin was expressed constitutively in both the normal mammary glands and the cleared fat pads. Unlike milk proteins, longer treatment with PRL (36 days of pituitary grafting) did not increase the expression level of CBP90 mRNA, while it slightly increased the cortactin mRNA level. Mammary CBP90 mRNA expression was induced by pituitary grafting but not by progesterone treatment in PRL-deficient mice, while pituitary grafting induced mammary CBP90 expression in ovariectomized PRL-deficient mice only when estrogen and progesterone were appropriately supplemented to permit the formation of alveolar buds. The CBP90 protein was detected by immunohistochemistry in the luminal epithelium of the alveolar buds and more faintly in the ductal epithelium. Thus, from the unique expression pattern, CBP90 may be useful as a molecular marker for the hormone-stimulated development of mammary alveolar buds.

The contents of mRNAs encoding LHβ-, FSHβ-, TSHβ- and common α-subunit precursor molecules were measured in food-deprived and subsequently re-fed male Japanese quail. Pituitary LHβ, FSHβ and common α mRNA levels were decreased by starvation, and increased to the control levels by re-feeding. The rates of decreases of LHβ and common α mRNA levels were greater the corresponding rate for FSHβ levels. Pituitary TSHβ mRNA levels were not decreased by starvation, but increased transitorily by re-feeding. Plasma LH and triiodothyronine levels were decreased by starvation, and then increased to control levels by re-feeding, while plasma FSH and thyroxine levels did not show significant changes. Plasma LH and FSH levels showed positive correlations with pituitary common α and FSHβ mRNA levels, respectively, while plasma thyroxine levels showed a negative correlation with TSHβ mRNA levels. Hepatic weight was decreased slightly but significantly by starvation, and then showed a remarkable rebound after re-feeding was started. These results suggest that LH synthesis and secretion are more sensitive to starvation than FSH synthesis and secretion in Japanese quail, and that LH production recovered to initial levels within several days when birds were fully fed. Also, there is a possibility that the synthesis of TSH is accelerated transitorily by re-feeding. Furthermore, these results showed that there are different relationships between the plasma levels of LH, FSH, and TSH and the various hormone subunit mRNA levels. The remarkable change in hepatic weight leads us to assume that hepatic thyroid hormone metabolism is affected by starvation and re-feeding.

A new species of echinoderid kinorhynch, Echinoderes sensibilis, is described and illustrated using light and electron microscopy. The specimens were collected from masses of the red algae Corallina pilulifera growing in intertidal pools in Tanabe Bay, Honshu Island, Japan. Diagnostic characters of E. sensibilis include the presence of middorsal spines on segments 6–10; lateral spines/tubules on segments 4, 7–12; remarkable trapezium-like subventral fields of minute cuticular hairs on segments 5-12. The positions of numerous sensory spots, large sieve areas, glandular tubes and the shape of terminal tergal and sternal extensions are also diagnostic. All taxonomic characters used for this description are illustrated by SEM. Echinoderes sensibilis constitutes the fifty-eighths valid species of the genus Echinoderes and the fourteenth species described from the Pacific Ocean. This is the third representative of Pacific kinorhynchs found only in the intertidal zone and the first Pacific Echinoderes living on red macroalgae in inter-tidal pools.

We analyzed population subdivision and gene flow of the Southeast Asian house mouse (Mus musculus castaneus) in Taiwan by using six microsatellite DNA markers. Seven populations of the house mouse (187 individuals), including one from Fukien Province in southeastern China, which is separated from Taiwan by the Taiwan Strait, were analyzed in this study. The overall polymorphic level at the six loci was high (H_e=0.76) although individual populations varied in their levels of heterozygosity (H_e=0.35–0.83). For the populations within Taiwan, there was no evidence of isolation by distance and the level of gene flow was not (inversely) correlated to geographic distances. Gene flow was estimated to be higher across the Taiwan Strait than within the island of Taiwan. These observations of gene flow cannot be understood unless in the context of the historical human settlements and agricultural expansion, and the commensal habits of the species. We also discussed the causes of population subdivision and genetic variation among populations in terms of ecological characteristics of the house mouse in Taiwan.

To illustrate phylogeography of red deer (Cervus elaphus) populations of Xinjiang, we determined their mitochondrial DNA (mtDNA) control region sequences, and then investigated geographic variations and phylogenetic relationships between Xinjiang populations and other populations from Asia, Europe, and North America. The C. elaphus mtDNA control region shared different copy numbers of tandem repeats of 38 to 43-bp motifs which clearly distinguished the Western lineage from the Eastern lineage of this species in Eurasia. The western lineage comprised the Tarim populations from southern Xinjiang and the European populations, all of which had four copies of the motifs. By contrast, the Eastern lineage consisted of populations from northern Xinjiang (Tianshan and Altai Mountains), other Asian areas (Alashan, Gansu, Tibet, Mongolia, and northeastern China), and North America, all of which shared six copies of the motifs. MtDNA phylogenetic trees showed that there are two major clusters of haplotypes which referred to the Western and Eastern lineages, and that subgroupings of haplotypes in each cluster were congruent with their geographic distributions. The present study revealed that a boundary separating the Western lineage from the Eastern lineage occurs between Tarim Basin and Tianshan Mountains in Xinjiang. Meanwhile, North American populations were genetically closer to those of northern Xinjiang, northeastern China, and Mongolia, supporting that C. elaphus immigrated from northeastern Eurasia to North America through the glacier-induced land-bridge (Beringia) which had formed between the two continents after Late Pleistocene.