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1.
DNA甲基化参与调节动物配子发生和胚胎发育过程,TET基因负责DNA主动去甲基化,在基因印迹去除和细胞全能性获得中起重要作用。为了解海洋贝类配子发生和胚胎发育过程中DNA去甲基化如何发生,本研究以虾夷扇贝为研究对象,鉴定了其TET基因,并分析了该基因在性腺和胚胎幼虫发育中的表达变化。结果表明,虾夷扇贝基因组中含有1个TET基因(PyTET),该基因长39127 bp,包含10个外显子,编码1592个氨基酸,其蛋白具有完整的2OGFeDO超家族的加氧酶结构域。在性腺发育过程中,PyTET基因表达峰值出现在休止期精巢和增殖期卵巢,原位杂交结果显示其在精原细胞、精母细胞中均有表达,在卵母细胞中的表达明显高于卵原细胞;在早期发育过程中,其峰值出现在囊胚期。以上结果提示虾夷扇贝配子发生和胚胎发育过程中均发生了DNA主动去甲基化,这将有助于系统了解表观调控在贝类发育中的作用。  相似文献   
2.
采用RNAi技术研究了栉孔扇贝(Chlamysfarreri)foxl2基因在卵子发生和卵巢功能维持中的作用。使用体外合成的栉孔扇贝foxl2双链RNA(dsRNA),以每只50μg/次的剂量注射进闭壳肌中,连续注射2次(第一次注射后7天,再进行第二次注射);以注射相同体积PBS(相同注射方法)的扇贝作为阴性对照组,以不注射扇贝作为空白对照组。qRT-PCR检测干扰组扇贝卵巢中的foxl2 mRNA表达量较空白对照组下降了62%, Western blotting检测该蛋白在卵巢中的含量也明显下降,显示靶基因的表达水平被有效地敲降。组织学观察发现,栉孔扇贝foxl2干扰后的卵巢中卵母细胞形态异常、细胞核固缩,卵子发生明显受阻。表明该基因在栉孔扇贝卵子发生中起重要作用。  相似文献   
3.
为了建立生态、高效的扇贝幼虫附着和变态诱导技术,采用底栖硅藻生物膜附着基对栉孔扇贝和海湾扇贝开展了附着和变态诱导的现场实验。实验围绕底栖硅藻在扇贝幼虫培育池内的数量变动、存活状态、在栉孔扇贝食谱组成中的贡献以及其对两种扇贝附着和变态的诱导效果开展。结果表明,底栖硅藻附着基能极显著提高海湾扇贝和栉孔扇贝幼虫的附苗量和变态率(P<0.01)。在海湾扇贝实验中,底栖硅藻处理组比对照组附苗量提高220.19%(P<0.01),变态率和壳长两组差异不显著(P>0.05)。在栉孔扇贝实验中,底栖硅藻处理组比对照组附苗量提高43.02%(P<0.01),变态率提高87.31%(P<0.01),底栖硅藻处理组壳长和对照组差异不显著(P>0.05)。对照组附着基比对照组早3d检查到变态的稚贝。底栖硅藻附着基在进入幼虫培育池的黑暗环境后光合作用受限,对于扇贝幼虫的日常管理导致底栖硅藻脱落,数量有一定的下降,但丰度最终能保持为56.0-183.9个/mm2。使用基于混合模型对栉孔扇贝稚贝食物来源进行分析结果显示金藻Isochrysis galbana对稚贝的食物贡献较高,底栖硅藻的贡献较低,其0.95水平的置信区间的贡献率为0%-44%,表明底栖硅藻也是扇贝物来源之一。本研究为底栖硅藻生物膜在贝类幼虫附着变态过程中作用的研究奠定了良好的基础,并为生态、高效的商业化苗种培育提供理论和技术支撑。  相似文献   
4.
于2009年3月至2010年1月期间,每月中旬分别从青岛和威海两地区采集人工养殖和野生的栉孔扇贝(Chla-mys farreri)。采集的扇贝经壳长测量后,于闭壳肌血窦中取血,离心,重悬,超声波破碎后制得血细胞破碎液。从抗栉孔扇贝血细胞的单克隆抗体库中筛选出1株与颗粒血细胞和透明血细胞均能结合,并能与血细胞多个蛋白结合的单克隆抗体作为酶联免疫吸附法(ELISA)中的第一抗体;第二抗体为碱性磷酸酶标记的羊抗鼠抗体。将血细胞破碎液包被于酶标板孔中,经一抗、二抗孵育后,显色读数,分析血细胞数量与生长的关系。结果表明:两地区人工养殖和野生扇贝的壳长均由3月的2 cm左右增长到了次年1月的7 cm以上,其中4~7月增长较快,而8~1月相对缓慢。两地区人工养殖和野生扇贝的血细胞数量于3~6月间均维持在较高的水平,6月达到最高峰,随后急剧下降,并于8或9月达到最低值,此后10~1月有所回升,但仍显著低于3~6月的水平。结论认为:栉孔扇贝血细胞数量与生长的关系在两地区、两扇贝品种间差别不大;但3~6月栉孔扇贝生长较快,血细胞数量相对高;而8~10月栉孔扇贝生长缓慢,其血细胞数量较低。  相似文献   
5.
本研究建立了一种高效、经济的非损伤性扇贝DNA提取方法,在不影响扇贝个体生存状态的前提下,采用擦拭法和室温裂解相结合的方式在20 min内即可获得个体基因组DNA。以虾夷扇贝(Patinopecten yessoensis)、栉孔扇贝(Chlamys farreri)和海湾扇贝(Argopecten irradians)为实验对象,研究了不同擦拭材料(棉签、滤纸)和不同擦拭部位(外套膜、鳃丝、内脏团)的核酸提取效果,评估了本方法在贝类基因分型领域应用的可行性。研究表明,用棉签、滤纸2种材料擦拭扇贝的鳃丝、内脏团或外套膜组织均能获得主带清晰完整的基因组DNA,且不影响扇贝的存活状态。在3种扇贝中采用棉签擦拭法的DNA得率均高于滤纸法,以这2种方式获得的DNA为模板进行SSR和SNP标记分析,能获得均一稳定的扩增条带,SSR标记分型结果准确可靠。本研究建立了简便、快速进行扇贝基因型分析的非损伤性DNA提取方法,为贝类全基因组选育和珍稀贝类资源的种质保护开发提供了新的技术手段。  相似文献   
6.
高温刺激导致虾夷扇贝死亡因素的探究   总被引:2,自引:0,他引:2  
本文探究了高温刺激导致一龄和二龄虾夷扇贝死亡的原因。在高温刺激以及恢复过程中,两种贝龄的扇贝存活率存在显著差异(P0.05),同时两者的谷丙转氨酶(glutamic-pyruvic transaminase,GPT)活性、p53蛋白含量、总抗氧化能力(total antioxidant capacity,TAOC)以及HSP70(heat shock protein 70)含量在高温刺激以及恢复过程中的变化均存在显著差异。而且这些酶的活性(TAOC活性除外)以及蛋白质含量(p53以及HSP70)均受到贝龄、处理时间以及两者综合作用的显著影响。经过Cox模型分析可知,虾夷扇贝受到高温刺激后的存活受到贝龄、GPT活性、TAOC活性、p53含量以及HSP70含量的显著影响。此外,高温刺激会影响扇贝的心跳频率以及心输出量,从而影响心脏对机体的供氧供血能力,影响扇贝对高温的适应能力。  相似文献   
7.
Cytochrome P450 (CYP) superfamily is one of the membership largest and function most diverse protein superfamily recogniozed among living beings. Members of this superfamily were further assigned to different families and subfamilies based on their amino acid similarities. According to their phylogenetic relationships, the CYP genes which likely diverged from common ancestor gene and may share common functions were grouped into one clan. Widely distributing scallops are a group of the most conspicuous bivalve; however the studies on their CYP is acarce. In this study, we searched the genome and expressed sequence tags of Zhikong scallop (Chlamys farreri) for CYP genes. In total, 88 non-redundant CYP were identified, which were homed in 13 CYPs gene families. Phylogenetic analysis divided these genes into 4 CYP clans. As in deuterostomes, Clan 2 was the largest, which contained 33 genes belonging to CYP1, CYP2, CYP17 and CYP356 families. Clan 3 contgained 19 genes belonging to CYP3, CYP5 and CYP30 families. Clan 4 contained 23 genes, all belonging to CYP4 family. The mitochondrial CYP clan contained 9 genes belonging to CYP10 and CYP24 families. In comparison, protostomes (C. farreri, D. pluex, D. melanogaster) contained more CYP genes than deuterostomes (S. purpuratus and vertebrates) in Clan 2 but less genes in Clan 3 and Clan 4. Our findings will aid to deciphering CYP function and evolution in scallops and bivalves.  相似文献   
8.
Zhikong scallop(Chlamys farreri) is an important maricultured species in China.Many researches on this species,such as population genetics and QTL fine-mapping,need a large number of molecular markers.In this study,based on the expressed sequence tags(EST),a total of 300 putative single nucleotide polymorphisms(SNPs) were selected and validated using high resolution melting(HRM) technology with unlabeled probe.Of them,101(33.7%) were found to be polymorphic in 48 individuals from 4 populations.Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500.The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505,respectively.Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers.BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs.Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons(33 SNPs) or pretermination of translation(1 SNP).The markers developed can be used for the population studies and genetic improvement on Zhikong scallop.  相似文献   
9.
Shells of commercially valued bivalves in New Zealand, Crassostrea gigas, Perna canaliculus and Pecten novaezelandiae, are damaged by blister-causing Polydora polychaete species known to be close in morphology to the widely recorded oyster pest Polydora websteri Hartman. Recent New Zealand occurrences are here confirmed to relate to two species, P. websteri, and a second similar species, Polydora haswelli Blake & Kudenov, a new record for New Zealand, previously known only from Australia; the two species are described and compared. The worms have limited distributions, with P. websteri confirmed only for Pacific oysters (C. gigas) in northern New Zealand, although prior reports indicate it may also occur on scallops and have reached the northern South Island. Polydora haswelli has been found only in northern New Zealand, occurring on subtidal mussels and scallops and native oysters (Perna canaliculus, Pecten novaezelandiae, Ostrea chilensis), as well as co-existing with intertidal P. websteri on Pacific oysters. The worms are not present in Foveaux Strait O. chilensis beds, a major source of past oyster exports to Australia. The history of mud-blister worm outbreaks in Australasia is examined. While trans-Tasman exports of live oysters from New Zealand were commonplace during the nineteenth century, there is no evidence that mud-blister worms were present in New Zealand then. The earliest reports only date from the early 1970s and only from northern New Zealand, whereas a century earlier in the 1870s at least one of these pest worms had become widespread along eastern Australian coasts.  相似文献   
10.
Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2 d) in Ps-c cultures, with a maximum of 119.7 g/(m2 d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.  相似文献   
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