Electrophoretic evaluation of the taxonomic status of two species of sea anemone

Puerto Rican populations of two species of sea anemones (Bunodosoma cavernata and B. granulifera) which had previously been considered one were assayed electrophoretically for enzymes encoded by 12 loci. The two species shared no common allozymes at 6 of the 12 loci. Genetic distance and identity values based on these allozymes were computed for the Puerto Rican populations and for B. cavernata from Florida and B. granulifera from Panama. The Puerto Rican populations of both species had much higher genetic identities for their geographically distant conspecifics than for each other. These results indicate that the two species are reproductively isolated and should be considered as separate valid species. Average heterozygosities are presented which are the first published for coelenterate species.     

Comparative ultrastructure of catch tentacles and feeding tentacles in the sea anemone Haliplanella

TEM observations of catch tentacles revealed that the tentacle tip epidermis is filled with two size classes of mature holotrich nematocysts and a gland cell filled with electron-dense vesicles. Vesicle production is restricted to upper-middle and tentacle tip regions, whereas holotrich development occurs in the lower-middle and tentacle base regions. Thus, catch tentacles have a maturity gradient along their length, with mature tissues concentrated at the tentacle tip. Occasional feeding tentacle cnidae (microbasic p-mastigophores and basitrichs) and mucus gland cells occur in proximal portions of catch tentacles, but are phagocytized by amoeboid granulocytes and transported to the gastrodermis for further degradation. No feeding tentacle cnidae or mucus cells occur distally in catch tentacles. Unlike catch tentacles, feeding tentacles are homogeneous in structure along their length with enidocytes containing mature spirocysts, microbasic p-mastigophore or basitrich nematocysts distributed along the epithelial surface. Cnidoblasts are recessed beneath cnidocytes, occurring along the nerve plexus. Mucus gland cells and gland cells filled with electron-dense vesicles are present in feeding tentacles, distributed at the epithelial surface. Granular phagocytes are rare in the feeding tentacle tip, but common in the tentacle base.     

Prolein polymorphism in a randombred chicken population

Polymorphism in plasma amylase, plasma alkaline phosphatase, non-specific esterase and red cell esterase-D of the Athens-Canadian randombred (ACRB) population of chickens was determined by polyacrylamide and starch gel electrophoresis. Amylase alleles Amy-1^A and Amy-1^B were segregating in the ACRB population with frequencies of 0.45 and 0.55 respectively. For the plasma alkaline phosphatase the F and S bands, the B band and a new isozyme migrating at a faster rate than the previously reported F band were detected. A genetic nomenclature for plasma alkaline phosphatase is suggested which considers the difference between the F and S bands as the presence or absence of sialic acid attached to a primary protein.
Plasma esterase activity was observed in all four of the regions previously reported, but there was no polymorphism found in any of the loci. All birds in this population showed the same red-cell esterase-D phenotype which consisted of a main band with sub-bands on each side.     

Chemical transmission in the sea anemone Nematostella vectensis: A genomic perspective

The sequencing of the starlet sea anemone (Nematostella vectensis) genome provides opportunities to investigate the function and evolution of genes associated with chemical neurotransmission and hormonal signaling. This is of particular interest because sea anemones are anthozoans, the phylogenetically basal cnidarians least changed from the common ancestors of cnidarians and bilaterian animals, and because cnidarians are considered the most basal metazoans possessing a nervous system. This analysis of the genome has yielded 20 orthologues of enzymes and nicotinic receptors associated with cholinergic function, an even larger number of genes encoding enzymes, receptors and transporters for glutamatergic (28) and GABAergic (34) transmission, and two orthologues of purinergic receptors. Numerous genes encoding enzymes (14), receptors (60) and transporters (5) for aminergic transmission were identified, along with four adenosine-like receptors and one nitric oxide synthase. Diverse neuropeptide and hormone families are also represented, mostly with genes encoding prepropeptides and receptors related to varying closeness to RFamide (17) and tachykinin (14), but also galanin (8), gonadotropin-releasing hormones and vasopressin/oxytocin (5), melanocortins (11), insulin-like peptides (5), glycoprotein hormones (7), and uniquely cnidarian peptide families (44). Surprisingly, no muscarinic acetylcholine receptors were identified and a large number of melatonin-related, but not serotonin, orthologues were found. Phylogenetic tree construction and inspection of multiple sequence alignments reveal how evolutionarily and functionally distant chemical transmitter-related proteins are from those of higher metazoans.     

The effect of color polymorphism on mortality in the aphidMacrosiphoniella yomogicola

We examined body color polymorphism in the aphidMacrosiphoniella yomogicola from July to September 1993. We classified body color into eight types: green 1, green 2, red 1, red 2, white, orange, yellow and mist. The frequencies of body color varied with time and among patches of the host plant, yomogi (Artemisia spp.). Color diversity within a shoot was calculated using the Shannon diversity index. Of five usable data sets, three showed negative relationships between color diversity and mortality. The regression coefficients for two of these relationships were significant. No significant relationship between mortality and the number of aphids was found. The color diversity was not significantly related to a particular body color found on a yomogi shoot. Color polymorphism may be maintained because selection may favor a high color diversity on the host plant shoot.     

昆虫体色多型的分子调控机制

体色多型普遍存在于各昆虫类群,体色多型不仅是生物多样性的体现,而且多样的着色模式对于昆虫本身具有重要的生物学意义.研究体色多型对探讨昆虫遗传多态性、适应机制及生物进化等具有重要的意义.本文主要从昆虫体色多型的分子调控机制进行综述,以期为今后探讨昆虫多态性、适应机制及生物进化提供参考.     

Ultrastructure of nematocyst discharge in catch tentacles of the sea anemone Haliplanella luciae (Cnidaria: Anthozoa)

The mature nematocyst lies just beneath the cnidodyte plasma membrane. A microtubule array surrounds the nematocyst capsule just beneath the capsule tip. We propose that the array helps to hold the capsule at the cnidocyte cell surface until discharge. The undischarged capsule tip is sealed by three apical flaps, joined together along complex radial seams. The seams are filled with subunits that appear to bind the flaps together. Upon discharge, the flaps separate along the radial seams to permit thread eversion. The everted thread is lined on both sides by subunits that are stained by antimonate, indicating that they bind calcium. We suggest that, together, the subunits hold the uneverted thread in its folded and coiled configuration. Thread eversion would follow subunit uncoupling. The capsule and thread interiors of partially discharged nematocysts are stained by antimonate. In contrast, the capsule and thread interiors of fully discharged nematocysts are not stained by antimonate. Thus, nematocyst calcium might be injected into the target tissue where it is presumed to act in conjunction with nematocyst venom to promote cell death.     

青岛海葵强心活性多肽在毕氏酵母中的分泌表达

青岛海葵中存在两种具有增强心肌收缩功能的多肽类毒素（分别命名为Ap-QD1和Ap-QD2).通过分析已经得到Ap-QD2的氨基酸序列,按照毕氏酵母的偏爱密码子设计并合成了Ap-QD2的cDNA.将合成cDNA序列通过PCR扩增及一系列分子克隆操作导入毕氏酵母表达载体pPICZαA中,以电穿孔方法转化毕氏酵母GS115和KM71,并进行转化子的表型及高拷贝化筛选.其中的KM71(Mut^s)的转化子经摇瓶发酵,每升发酵液可表达约20 mg的重组Ap-QD2产物,通过纯化可得到7 mg纯的有天然生物学活性的Ap-QD2基因工程产物.     

The RHD variants in Chinese population

The Rhesus (Rh) blood group system is the most important blood group system in hemolytic disease of the fetus and newborn (HDFN). In clinical transfusions, the D antigen in the Rh blood group system comes third, behind antigens A and B which from ABO blood group system. Over the past decade, molecular technologies have been used to investigate the RHD allele in different ethnic groups. This review first introduces the basic structure of RhD protein and coding genes, then focuses on D-negative, weak D, partial D, DEL, RhD_null variants reported in the Chinese population. To date, more than 460 RHD variants have been reported around the world, but less than 70 RHD variants have been reported in the Chinese population. Further research is needed to identify more RHD polymorphism and establish criteria for blood detection and transfusion guidelines for RHD variants. Only in this way can we better guarantee the safety of blood transfusion and prevent the occurrence of HDFN. With the accumulation of research and clinical data, we should be clearer which RHD variants are to be regarded as RhD negative and which need to be regarded as RhD positive.     

A multispecies BCO2 beak color polymorphism in the Darwin’s finch radiation

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Antagonistic selection factors induce a continuous population divergence in a polymorphism

Understanding the relative importance of selection and stochastic factors in population divergence of adaptive traits is a classical topic in evolutionary biology. However, it is difficult to separate these factors and detect the effects of selection when two or more contrasting selective factors are simultaneously acting on a single locus. In the damselfly Ischnura senegalensis, females exhibit color dimorphism and morph frequencies change geographically. We here evaluated the role of selection and stochastic factors in population divergence of morph frequencies by comparing the divergences in color locus and neutral loci. Comparisons between population pairwise F_ST for neutral loci and for the color locus did not detect any stochastic factors affecting color locus. Although comparison between population divergence in color and neutral loci using all populations detected only divergent selection, we detected two antagonistic selective factors acting on the color locus, that is, balancing and divergent selection, when considering geographical distance between populations. Our results suggest that a combination of two antagonistic selective factors, rather than stochastic factors, establishes the geographic cline in morph frequency in this system.     

Discovery of androecium color polymorphism in Epimedium pubescens with habitat preference of anther/pollen color in the genus

Aims Interspecific and intraspecific variation in flower color in natural populations provides an opportunity for us to understand the evolution and maintenance of diversity of floral traits. Compared to corolla color, little is known about the color polymorphism of sexual organs in flowering plants. To explore evolutionary transitions of androecium color and polymorphism within species, interspecific and intraspecific variation in androecium (anther and pollen) color in the genus Epimedium (Berberidaceae) was investigated.Methods To explore the geographical patterns of anther/pollen color variation in Epimedium species, data of 45 species were collected and their phylogeny was constructed based on available DNA sequences. To investigate whether intraspecific variation in androecium color relates to habitat preference, three environmental factors were measured in the field population of Epimedium pubescens in northeastern Sichuan, China, which plants had green or yellow androecia. Vegetative and reproductive traits of this species were compared between the two color morphs.Important findings Androecium (anther and pollen) color polymorphism in field populations of Epimedium pubescens is reported here where nine populations are monomorphic with a green androecium but three populations are dimorphic with individuals having either a green or a yellow androecium. Inflorescence stalk height, stalk diameter, leaf number, flower number and spur length (as well as spur and nectar volume) were not significantly different between two morphs. Compared to the yellow morph, the green morph had relatively larger leaves and anthers, but smaller sepals. The green morph produced more pollen and larger seeds, but the same number of ovules. Seed set was not significantly different between green and yellow morph. Investigations of environmental factors in the color dimorphic populations of E. pubescens indicated that the green morph was more likely to occur in habitats with relatively lower light intensity. The distribution survey of 45 Epimedium species showed that species with a green androecium tended to appear at lower elevations. Comparative phylogenetic analysis showed that transitions from yellow to a green androecium or to androecial color dimorphism occurred at least seven times. This genus, characterized by anther color diversity and containing some species with anther color polymorphism, provides a model system in which to study the evolution and maintenance of colorful sexual organs in flowering plants.     

The functional significance of a stigma color polymorphism in Acer pictum subsp. mono (Aceraceae)

Aims Exploring the characteristics and function of a flower color polymorphism contributes to our understanding of floral evolution in angiosperms. However, little information is available on stigma color polymorphisms in flowering plants despite their important functional role in plant reproduction.Methods We studied a stigma color polymorphism at the individual level in Acer pictum subsp. mono (aka A. mono) by investigating stigma-color morph proportion and comparing stigma performance and components of female fitness (pollen adhesion, pollen germination, fruit set, seed set and fruit weight) between the two morphs (red and greenish-yellow stigma) within natural populations at Dongling Mountain in the north of China. In the flowering period, we conducted hand pollination in natural populations and then made microscopic observations using the aniline blue fluorescence method.Important findings Individuals in the studied populations did not change their stigma color between years, and flowers produced by a single tree were uniform in their stigma color. This strongly suggests that stigma color variation is genetically controlled. The percentage of the red stigma flowers with germinated pollen grains was significantly higher than that of the greenish-yellow stigma flowers when hand pollination was conducted in the early flowering period, but not so in the late flowering period. There was no significant difference in the percentage of flowers with pollen adhesion to the stigma between the two morphs. Fruit set of the red morph was significantly higher than that of the greenish-yellow morph. Our findings suggest that the red morph may be more advantageous for pollen germination and fruit set than the greenish-yellow morph, which may provide a functional explanation for the high incidence of the red stigma morph in the studied populations. Alternative explanations for the stigma color polymorphism are discussed to stimulate further work.     

山樱花品种间花色差异的代谢组学研究

山樱花是世界著名的观花类植物,花色是其最重要的观赏特征。为探究影响山樱花品种间花色差异的代谢通路及关键代谢产物变化,该文利用LC-MS/MS技术对白色、绿色和粉色的山樱花品种进行花青素靶向代谢组学比较分析。结果表明：(1)共检测到42种花青素物质,主要包含矮牵牛素、飞燕草素、黄酮类化合物、锦葵色素、芍药花素、矢车菊素、天竺葵素和原花青素8种物质。(2)差异代谢花青素25种,包括11种下调、14种上调,其中有7种花青素在粉色花瓣中显著富集。(3)KEGG通路注释发现差异代谢物在花青素生物合成通路中显著富集,结合聚类结果发现矮牵牛素-3-O-葡萄糖苷是山樱花品种间花色差异产生的关键代谢物。该研究揭示了山樱花花色差异的代谢机理,为后续山樱花花色分子调控机制研究提供了一定的理论依据,也为新品种花色改良和选育提供了一定的科学参考。     

枫香秋季变色期叶色变化及其生理基础

为探究秋季枫叶呈色的关键生理因素,该文以转色期叶色为绿色、黄色和红色的枫香单株为试材,研究了L^*、a^*、b^*值变化与叶片色素、可溶性糖及可溶性蛋白质含量变化的相关性。结果表明:(1)在变色期,3种色彩枫香叶片叶绿素a、叶绿素b、总叶绿素和类胡萝卜素均大量降解,花色素苷不同程度积累。(2)绿色叶单株叶绿素和类胡萝卜素始终保持较高含量,花色素苷含量上升4.2倍,叶片内色素含量比值始终保持稳定; 黄色叶单株叶绿素和类胡萝卜素含量最低,花色素苷含量上升4.4倍,b^*值与叶绿素含量极显著负相关,与类胡萝卜素含量显著负相关,与花色素苷/类胡萝卜素含量比值极显著正相关; 红色叶单株叶绿素和类胡萝卜素含量略高于黄色叶单株,花色素苷含量上升27.2倍,a^*值与叶绿素含量、类胡萝卜素含量极显著负相关,与花色素苷含量显著正相关,与色素含量比值无显著相关性。(3)红色叶单株具有较高的可溶性糖含量和可溶性蛋白质含量。因此,在枫香叶片变色期,保持较高的叶绿素和类胡萝卜素含量,维持色素含量比值稳定使叶片呈现绿色; 叶绿素和类胡萝卜素的大量降解,以及花色素苷/类胡萝卜素含量比值的升高使叶片呈现黄色; 叶绿素的降解和花色素苷的大量合成使叶片呈现红色。     

Discovery of gynoecium color polymorphism in an aquatic plant

Flower color polymorphlsm exhibited by natural populations provides an opportunity for understanding the evolutionary mechanisms contributing to the diversity of floral morphology.However,little is known about the color polymorphism of female organs in flowering plants.Here we report gynoecium color polymorphism in Butomus umbellatus (Butomaceae),an emergent,aquatic monocot.Populations from Mishan,northeastern China comprised two morphs; gynoecia are either pink,as observed in other areas,or white.We measured floral traits and female fecundity in the two gynoecium color morphs in the field.There was no significant difference in plant height,pedicel length,and flower size including petal,sepal and gynoecium between the two morphs,but plants with pink gynoecia had wider inflorescence stalks,larger inner whorl anthers and produced more pollen and ovules than those with white gynoecia.Correspondingly,we found that seed production was significantly higher in the pink than in the white morph.This new finding suggested selection against white gynoecia in part because of low fecundity,consistent with the rarity of the white gynoecium morph in this species.     

Protein polymorphism and genic variation in a population of the loach Cobitis delicata

Hemoglobin, non-enzymatic and enzymatic muscle proteins of the loach Cobitis delicata were examined electrophoretically. Eleven proteins were shown to be under control by 20 loci. Only two loci were defined as polymorphic and 14 loci were completely monomorphic. Estimated average heterozygosity over all 20 loci was 0.011 in the loach population.     

Fruit color polymorphism in a bird-dispersed shrub (Rhagodia parabolica) in Australia

Summary We examined the selective basis of fruit color, a trait assumed to affect the attractiveness of fruits to avian dispersal agents, inRhagodia parabolica in Victoria, Australia. The fleshy fruits ofR. parabolica are highly polymorphic in color; individual plants may bear red, white, or yellow fruits, or some combination of these. Red color is produced by betacyanins, yellow by betaxanthins, and white by some other flavonoid compounds. Red is the most common color, white less common, and yellow is relatively rare; red and white is the most common color combination. Fruits of these color-morphs do not differ in maximum size, weight, pulp-seed ratio, water content, or content of major nutrients (sugars, N, and lipids). The most common avian consumer,Zosterops lateralis, foraged at random on the color-morphs, although all fruit-eaters, collectively, slightly favored white fruits. Weekly fruit removal rates were equivalent for all four morphs. Seeds from color-morphs differed in seed germination behavior: seeds from red fruits germinated faster than seeds from yellow fruits, and seeds from white fruits showed the greatest response to passage throughZ. lateralis guts. Lack of strong foraging preferences by birds and the different germination behaviors may contribute to the maintenance of the color polymorphism.     

Distribution of the Val108/158Met polymorphism of the COMT gene in healthy Mexican population

Catechol-O-methyltransferase (COMT) inactivates the catecholamines adrenaline, noradrenaline and dopamine. On the other hand, some studies have reported that the enzymatic activity of COMT is partly genetically determined. With regard to the COMT gene, the most studied polymorphism is the functional variant Val108/158Met (rs4680), which results in substantial three- to four-fold variations in enzyme activity. To date, the rs4680 polymorphism of COMT has been associated with a number of disorders. In addition, this polymorphism has been found to have important differences in frequency according to the studied population. Therefore, the aim of the present study was to evaluate the frequency of a common single nucleotide polymorphism (SNP) Val108/158Met of the COMT gene in the Mexican population. Accordingly, we recruited 431 healthy volunteers. Our sample consisted of 111 healthy individuals from Mexico City and 320 individuals from the state of Tabasco, Mexico. We observed that Met was the most common allele, ranging from 57% (Tabasco) to 85% (Mexico City). In addition, we analyzed the frequency of Val108/158Met polymorphism of Caucasian (54% Met allele), Asian (29% Met allele) and African (34% Met allele) populations separately and also in comparison with Mexican (63% Met allele) population. In conclusion, the distribution of the Val108/158Met polymorphism distinguishes the Mexican population studied from other populations, but it is necessary to increase the size of the sample to get more conclusive results.