Mnemonic function of the dorsolateral prefrontal cortex in conflict-induced behavioral adjustment

Our cognitive abilities in performing tasks are influenced by experienced competition/conflict between behavioral choices. To determine the role of the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC) in the conflict detection-resolution process, we conducted complementary lesion and single-cell recording studies in monkeys that were resolving a conflict between two rules. We observed conflict-induced behavioral adjustment that persisted after lesions within the ACC but disappeared after lesions within the DLPFC. In the DLPFC, activity was modulated in some cells by the current conflict level and in other cells by the conflict experienced in the previous trial. These results show that the DLPFC, but not the ACC, is essential for the conflict-induced behavioral adjustment and suggest that encoding and maintenance of information about experienced conflict is mediated by the DLPFC.     

Anterior cingulate conflict monitoring and adjustments in control

Conflict monitoring by the anterior cingulate cortex (ACC) has been posited to signal a need for greater cognitive control, producing neural and behavioral adjustments. However, the very occurrence of behavioral adjustments after conflict has been questioned, along with suggestions that there is no direct evidence of ACC conflict-related activity predicting subsequent neural or behavioral adjustments in control. Using the Stroop color-naming task and controlling for repetition effects, we demonstrate that ACC conflict-related activity predicts both greater prefrontal cortex activity and adjustments in behavior, supporting a role of ACC conflict monitoring in the engagement of cognitive control.     

哺乳动物ACCα基因启动子结构特征及调控

乙酰辅酶A羧化酶(ACC)在哺乳动物脂肪酸合成和分解代谢中发挥着重要作用.ACC包括ACCα和ACCβ2种形式,由不同基因编码,其中ACCα主要在脂肪酸合成过程中起作用.哺乳动物ACCα基因的启动子主要包括3个:PⅠ、PⅡ和PⅢ,而反刍动物和啮齿动物还包括第4个启动子PIa,各启动子具有不同的结构特征.     

植物ACC合成酶在大肠杆菌中高效表达及表达产物活性测定

丝瓜ACC合成酶cDNA在T7启动子的作用下 ,经IPTG诱导 ,在大肠杆菌中高效表达 ,表达外源蛋白可占菌体总蛋白的 45 2 % .表达的ACC合成酶一部分以可溶的形式存在 ,具有与天然ACC合成酶相似的酶活性 ,将反应底物S 腺苷蛋氨酸 (SAM)转化为 1 氨基环丙烷 1 羧酸 (ACC)并在细菌培养基中积累 ,另一部分则以无活性的包涵体形式存在于菌体中 .     

植物ACC合成酶在大肠杆菌中高效表达及表达产物活性测定

丝瓜ACC合成酶cDNA在T7启动子的作用下，经IPTG诱导，在大肠杆菌中高效表达，表达外源蛋白可占菌体总蛋白的45.2%.表达的ACC合成酶一部分以可溶的形式存在，具有与天然ACC合成酶相似的酶活性，将反应底物S-腺苷蛋氨酸(SAM)转化为1-氨基环丙烷-1-羧酸(ACC)并在细菌培养基中积累，另一部分则以无活性的包涵体形式存在于菌体中.     

椰子乙酰CoA羧化酶(ACC)基因的鉴定及表达分析

[目的]克隆椰子的乙酰Co A羧化酶(ACC)基因.[方法]通过已发表的椰子转录组注释结果,鉴定潜在的椰子ACC基因.分析ACC基因在椰子果肉和嫩叶混合样转录组中的RPKM值,同时,采用实时定量PCR技术研究5个高RPKM值的ACC基因在椰子果肉发育的不同时期的表达情况.[结果]共获得21个椰子的ACC基因,这21个ACC基因在椰子果肉和嫩叶混合样品中有较高的表达量,4个ACC基因(Unigene7806、Unigene47155、Unigene7847和CL185.Contig1)在椰子果肉发育9个月时表达量最高.[结论]该研究为解析椰子脂肪酸积累的分子机制提供了前期工作基础.     

Performance monitoring by the anterior cingulate cortex during saccade countermanding

Consensus is emerging that the medial frontal lobe of the brain is involved in monitoring performance, but precisely what is monitored remains unclear. A saccade-countermanding task affords an experimental dissociation of neural signals of error, reinforcement, and conflict. Single-unit activity was monitored in the anterior cingulate cortex of monkeys performing this task. Neurons that signaled errors were found, half of which responded to the omission of earned reinforcement. A further diversity of neurons signaled earned or unexpected reinforcement. No neurons signaled the form of conflict engendered by interruption of saccade preparation produced in this task. These results are consistent with the hypothesis that the anterior cingulate cortex monitors the consequences of actions.     

TRB3 links the E3 ubiquitin ligase COP1 to lipid metabolism

During fasting, increased concentrations of circulating catecholamines promote the mobilization of lipid stores from adipose tissue in part by phosphorylating and inactivating acetyl-coenzyme A carboxylase (ACC), the rate-limiting enzyme in fatty acid synthesis. Here, we describe a parallel pathway, in which the pseudokinase Tribbles 3 (TRB3), whose abundance is increased during fasting, stimulates lipolysis by triggering the degradation of ACC in adipose tissue. TRB3 promoted ACC ubiquitination through an association with the E3 ubiquitin ligase constitutive photomorphogenic protein 1 (COP1). Indeed, adipocytes deficient in TRB3 accumulated larger amounts of ACC protein than did wild-type cells. Because transgenic mice expressing TRB3 in adipose tissue are protected from diet-induced obesity due to enhanced fatty acid oxidation, these results demonstrate how phosphorylation and ubiquitination pathways converge on a key regulator of lipid metabolism to maintain energy homeostasis.     

草莓体内高ACC脱氨酶活性菌株的分离及鉴定

[目的]分离草莓体内具有较高ACC脱氨酶活性的菌种,丰富具有果蔬保鲜价值的植物内生菌资源。[方法]采用ADF培养基分离具有ACC脱氨酶活性的细菌,并且用生理生化和分子生物学方法进行鉴定,将具有ACC脱氨酶活性的菌株在草莓中定植。[结果]分离出具有ACC脱氨酶活性的内生细菌23株,其中CJL1菌株的ACC脱氨酶活性最高,比活力达0.142U/mg。CJL1菌株为成团泛菌,能够在草莓体内稳定地定植。[结论]成功地在草莓体内分离得到具有高ACC脱氨酶活性并能定植的成团泛菌。     

果实发育过程中乙烯的合成与调控

对果实发育过程中乙烯的合成与调控在分子水平上的研究进展进行了综述,特别是对乙烯合成过程中的3个关键酶ACC合成酶、ACC氧化酶和SAM合成酶以及信号传导对番茄果实成熟的影响进行了讨论。     

气调对猕猴桃果实采后乙烯生成的效应及其机制

气调贮藏条件下猕猴桃果实成熟延缓,组织内乙烯含量及乙烯生成速率明显低于对照,气调 处理抑制乙烯生成的效应主要通过抑制ＡＣＣ合成实现,也抑制ＡＣＣ氧化酶活性,降低ＡＣＯ／ＡＣＣ＋ ＭＡＣＣ）比值, ＡＣＣ含量是猕猴桃果实采后乙烯生成的限制因子。气调条件下果实组织内乙烯含量、 ＡＣＣ含量及ＡＣＣ氧化酶活性变化出现交替升降现象。     

油棕乙酰CoA羧化酶(ACC)基因的鉴定与表达分析

[目的]对油棕乙酰CoA羧化酶(ACC)基因进行鉴定与表达分析。[方法]采用生物信息学方法鉴定油棕的ACC基因,并应用拟南芥的ACC基因蛋白质序列比对油棕的蛋白质库,应用已有油棕转录组信息,研究ACC基因在不同组织中的表达情况。[结果]在油棕中鉴定了2个ACC基因,命名为EgACC1和EgACC2。EgACC1不含内含子,而EgACC2含有32个内含子;EgACC1在不同组织中都没有表达,而EgACC2在所有组织中都有表达,其中在组培苗中有较高的表达量,同时,在油棕果发育21 d时有高的表达水平,RPKM值为70.6,为所有组织中最高。[结论]该研究阐述了油棕ACC基因的表达模式,为油棕ACC基因的功能分析奠定了基础。     

RT-PCR半定量法检测大蒜素对肉仔鸡肝脏HMG-CoAR、ACC和FASmRNA表达的影响

通过RT-PCR半定量法分析大蒜素对肉仔鸡肝脏中与脂类代谢有关的3种酶HMG-CoAR、ACC和FASmRNA表达的影响.结果显示,大蒜素抑制了肉仔鸡肝脏中HMG-CoAR、ACC和FASmRNA表达,下降率分别为80.8%、 74.2%和64.1%.     

高等植物ACC氧化酶基因的克隆·表达及其调控

ACC氧化酶是调节乙烯生物合成的关键酶之一。文中主要对ACC氧化酶基因的克隆、表达调控及其在植物基因工程中的应用等方面进行综述,为通过分子生物学技术调控植物果实内乙烯的含量从而延长水果货架期提供思路。     

Does rejection hurt? An FMRI study of social exclusion

A neuroimaging study examined the neural correlates of social exclusion and tested the hypothesis that the brain bases of social pain are similar to those of physical pain. Participants were scanned while playing a virtual ball-tossing game in which they were ultimately excluded. Paralleling results from physical pain studies, the anterior cingulate cortex (ACC) was more active during exclusion than during inclusion and correlated positively with self-reported distress. Right ventral prefrontal cortex (RVPFC) was active during exclusion and correlated negatively with self-reported distress. ACC changes mediated the RVPFC-distress correlation, suggesting that RVPFC regulates the distress of social exclusion by disrupting ACC activity.     

蝴蝶兰ACC氧化酶和ACC合成酶融合反义表达载体的构建

为了获得具有超常花期的蝴蝶兰新品系,根据已报道的蝴蝶兰ACC合成酶(ACS)基因和ACC氧化酶(ACO)基因的序列,设计引物从蝴蝶兰总RNA中克隆出ACS保守区的461 bp片段和ACO的333 bp片段,完成2个基因的克隆和测序后,将ACS基因片段和ACO基因片段以反义的方向插入到中间载体pBI221 CaMV启动子...     

乙酰辅酶A羧化酶(ACC)的结构与功能

乙酰辅酶A羧化酶(ACC)催化乙酰辅酶A形成丙二酸单酰辅酶A的羧化作用,是在脂肪酸合成和代谢中起重要作用的中间代谢物。ACC包括ACCα和ACCβ两种形式,被不同的基因编码。ACC(α265 kDa)主要在脂肪生成活跃的肝脏、脂肪组织和乳腺中表达。ACC(β275 kDa)主要在β-氧化作为主要能量来源的骨骼肌和心脏中表达。对ACC的结构特点和基本功能进行了探讨。     

李果实成熟软化过程中生理特性及乙烯合成变化的研究

以乙烯合成途径为线索,研究李(Prunus domestica L.)果实成熟软化过程中硬度、可溶性固形物、可滴定酸、乙烯释放量、氨基环丙烷羧酸(ACC)和丙二酰氨基环丙烷羧酸(MACC)含量以及ACC合成酶(ACS)和ACC氧化酶(ACO)活性等指标的变化,探讨乙烯在李果实成熟软化中的作用。结果表明:李果实成熟软化过程中,硬度和可滴定酸的含量逐渐降低,可溶性固形物含量增加。李果实成熟期的软化启动阶段,乙烯释放量、ACC含量、ACS和ACO活性增强缓慢,此时乙烯释放量也比较低,ACS和ACO的活性都受到一定程度的抑制,在成熟过程中三者高峰值同时出现在软化后期。证明李果实成熟期的软化启动阶段,乙烯并非是软化启动因子,可能还存在其他的启动相关因子。     

黄河蜜甜瓜1-氨基环丙烷1-羧酸合成酶基因片段的克隆和反义载体的构建

从伤诱导的黄河蜜甜瓜(Cucumismelocv.Huanghemi)成熟果实的中果皮组织中分离总RNA,经反转录和PCR扩增得到974bp的cDNA片段,克隆到质粒载体pGEM-3zf,经测序与Genbank中甜瓜1-氨基环丙烷1-羧酸合成酶(1-amino-cyclopropane-1-carboxylieacidsynthase,ACS)基因同源性为99%。克隆片段经双酶切消化,反向插入到植物表达载体pBI121的35S启动子和NOS终止子之间,构建成ACS基因的反义表达载体。     

薄皮甜瓜果实ACC合成酶cDNA克隆及反义表达载体的构建

从成熟的薄皮甜瓜(Cucumis melo cv.Qitian I)果肉组织中分离总RNA,经RT-PCR扩增得到0.7 kb的cDNA片段,将其克隆到质粒载体pGEM-T Easy。测序表明,该基因为777 bp,编码258个氨基酸,与Gen-Bank中甜瓜1-氨基环丙烷-1-羧酸合成酶(1-aminocyclopropane-1-carboxylate synthase,ACS)基因比对,核苷酸同源性为99%,氨基酸同源性为98%。克隆片段经双酶切消化,反向插入到植物表达载体pCAM2301的E8启动子和NOS终止子之间,构建成E8调控下ACS基因反义表达载体。通过冻融法将携带反义cDNA的植物表达载体质粒转入根癌农杆菌LBA4404,得到了完整的Ti质粒表达载体系统。