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The tomato floral system is distinguished from that of Arabidopsis and Antirrhinum in several ways. The shoot is a sympodium, the first flower of the inflorescence is apical and no bracts are formed. We discuss the possible function of genes affecting growth habit and inflorescence development and analyze in detail the unique developmental alterations caused by inhibition or ectopic expression of tomato-specific MADS-box genes. Preliminary analysis of transgenic tomato plants expressing an alien homeotic gene and several different chimeric genes of the MADS-box family is also reported. 相似文献
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用同源克隆的方法和3′RACE技术,从日本晚樱(Prunus lannesiana)中分离得到了1个AP3同源基因PrseAP3的cDNA全长,GenBank登录号为JF710371。其cDNA全长977bp,包括1个编码235个氨基酸共708bp的开放阅读框。序列比对和分子系统发生分析表明,PrseAP3是拟南芥的AP3同源基因,其蛋白质的C末端具有2个保守基元:PI-derived模体和paleoAP3模体,属B类转录因子中paleoAP3进化系。半定量RT-PCR分析表明,PrseAP3主要在单瓣日本晚樱品种大岛的萼片、花瓣和雄蕊中表达;在重瓣品种一叶的花瓣、雄蕊和叶化心皮中表达。其表达组织特异性在2个品种间表现出明显的差异,并与拟南芥的AP3基因有一定的差别。 相似文献
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白菜型无花瓣油菜突变体的花器官形态特征 总被引：7，自引：1，他引：7
在我国白菜型油菜地方品种余井花籽和国外白菜型油菜品种Am032中同时发现了无花瓣突变体。通过对白菜型油菜无花瓣突变体与甘蓝型无花瓣油菜及正常油菜器官形态的鉴定和比较，认为白菜型油菜无花瓣突变体的花瓣缺失突变机制与甘蓝型油菜不同，白菜型油菜无花瓣突变体有花瓣转变成雄蕊的现象，推测白菜型油菜花瓣缺失突变可能与花器官同源异型基因突变有关。 相似文献
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以20a树龄同一梨园中1株能稳定遗传的花器官变异鸭梨和普通鸭梨为试材,采用形态观测法进行了花芽发育、花粉萌发率、表观形态等方面的研究分析。结果表明:该突变株的花发育与普通植株花的正常发育最明显的差别在于花器官花瓣完全或部分缺失、雄蕊相应增多;花瓣对应位置的雄蕊花丝粗、花药大;花粉萌发率高;部分特化的花瓣上着生有花药。根据试验结果,推断该突变株可能是梨的花同源异型突变株,控制花器官发育的B功能区发生了突变引起花器官异常。该突变株为进一步认识植物花发育的内在调控机制、研究花的发育机理提供了可能。 相似文献
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文冠果同源异型变异株的发现 总被引：7，自引：2，他引：7
该文对北京林业大学苗圃内发现的一文冠果的同源异型自然变异株进行了形态及解剖学观察．结果发现：这一花器官变异植株的花明显小于正常株的花,且不能完全开放,始终呈半开状．花重瓣多轮,仅具花萼和花瓣,不具雄蕊和雌蕊．因为雄蕊和雌蕊全部特化为花瓣状,部分特化的内轮花瓣上留有花药的残迹,花药内的花粉发育是不正常的．与此相关的营养体特征是变异株的叶片大,厚且颜色呈深黑绿色． 相似文献
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拟南芥(Arapidopsis)同源异型基因AP2对花分生组织和花器官的发育具有重要的表达调控作用。根据AP2基因信息利用同源序列法分离了油菜(Brassicarapa)的AP2基因(BAP2,GenBank登陆号:AF941097),并且比较了正常油菜与无花瓣油菜BAP2基因序列的差异。研究结果表明,BAP2基因的DNA序列长度为2138bp,包含9个内含子,外显子区与AP2基因的同源性达90%以上;推导的氨基酸序列为433aa,具有完整的核定位信号区和高度保守的AP2结构域,推测与AP2基因具有相似的功能。正常油菜和无花瓣油菜的BAP2基因序列仅有2处碱基存在差异,这2处碱基均位于内含子区,推导的氨基酸序列则完全一致,因此初步认为白菜型油菜花瓣缺失突变与BAP2基因无关。 相似文献
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EX VIVO COMPUTED TOMOGRAPHIC EVALUATION OF MORPHOLOGY VARIATIONS IN EQUINE CERVICAL VERTEBRAE 
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下载免费PDF全文 Stefanie Veraa Wilhelmina Bergmann Antoon‐Jan van den Belt Inge Wijnberg Willem Back 《Veterinary radiology & ultrasound》2016,57(5):482-488
Diagnostic imaging is one of the pillars in the clinical workup of horses with clinical signs of cervical spinal disease. An improved awareness of morphologic variations in equine cervical vertebrae would be helpful for interpreting findings. The aim of this anatomic study was to describe CT variations in left–right symmetry and morphology of the cervical and cervicothoracic vertebrae in a sample of horses. Postmortem CT examinations of the cervical spine for horses without congenital growth disorders were prospectively and retrospectively recruited. A total of 78 horses (27 foals, 51 mature horses) were evaluated. Twenty‐six horses (33.3%) had homologous changes in which a transposition of the caudal part of the transverse process (caudal ventral tubercle) of C6 toward the ventral aspect of the transverse process of C7 was present (n = 10 bilateral, n = 12 unilateral left‐sided, n = 4 unilateral right‐sided). There was one horse with occipito‐atlantal malformation, two horses with rudimentary first ribs bilaterally, and one horse with bilateral transverse processes at Th1, representing homeotic (transitional) vertebral changes. Chi‐square tests identified no significant differences in the number of conformational variations between the group of mature horses with or without clinical signs (P = 0.81) or between the group of mature horses and the group of foals (P = 0.72). Findings indicated that, in this sample of horses, the most frequently identified variations were homologous variations (transposition of the caudal part of the transverse process of C6–C7) in the caudal equine cervical vertebral column. Homeotic (transitional) variations at the cervicothoracic vertebral column were less common. 相似文献
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Floral induction in woody angiosperms 总被引：13，自引：0，他引：13
The long juvenile period of trees is a severe impediment to study of reproductive biology and genetic inheritance, and is a serious constraint for traditional breeding programs. Very little effort has been directed toward the development of practical methods for inducing early flowering in most woody angiosperms, particularly members of the genus Populus. This review is intended to stimulate interest in, and provide direction for, future research in this area. An emphasis is placed on techniques that can be applied easily and inexpensively. Inductive treatments discussed include: phytohormones (gibberellins, cytokinins, abscisic acid, ethylene and auxin); growth retardants (paclobutrazol, uniconazole, daminozide, chlormequat and cimecthacarb); physical constraints (girdling, root restriction and shoot training); cultural conditions (photoperiod, mineral nutrition, moisture stress and temperature); and grafting. Recent reports on stimulation of flowering by genetic transformation with floral homeotic genes are also described. Several research avenues which appear promising are proposed for near-term study. 相似文献
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【目的】研究不结球白菜雄蕊心皮化雄性不育系HGMS和甘蓝型无花瓣油菜雄蕊心皮化雄性不育系AMS的特征,探讨雄蕊心皮化突变机理。【方法】以HGMS和AMS为试材,进行形态特征、同工酶分析及其杂交研究。【结果】系内不育株HGMSa和AMSa均具有明显的雄蕊心皮化形态特征,且雄蕊心皮化器官酯酶、过氧化物酶同工酶酶带与雌蕊酶带相同。系内可育株HGMSb和AMSb雄蕊发育正常,但存在花瓣有、无的显著差异。相互杂交研究表明,引起HGMS和AMS雄蕊心皮化突变的基因位点是相同的。HGMSb调控花瓣、雄蕊发育的单基因与AMSb调控雄蕊发育的单基因虽然存在形成花瓣功能的明显差异,但具有相同的作用位点,对HGMSa和AMSa雄蕊心皮化性状均具有恢复作用。【结论】HGMSa和AMSa具有相同的雄蕊心皮化特征,而且引起雄蕊心皮化突变的基因位点是相同的。 相似文献
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