植物花距表型趋同进化和发育机制多样化的研究进展

doi:10.17520/biods.2023249

摘要/Abstract

摘要：

花距常被认为是植物适应传粉者而出现的一个关键创新性状。花距在被子植物中广泛分布, 并且不同物种花距形态存在较大差异。已有研究集中于探讨花距与传粉者间复杂的关系。本文介绍了花距的概念和功能, 并且描述了花距的形态、长度、颜色和内含物等特征的多样性; 阐述了造成种内和种间花距形态差异的原因; 总结了花距在形成和发育过程中一系列细胞和关键分子机制。结合花距在被子植物中的分布和花距形成位置的多样性以及发育分子机制, 阐明花距可能是多次起源, 具有趋同进化特征, 但是形成和发育方式在进化上不保守。最后, 本文提出了花距未来研究的方向: (1)构建被子植物花距表型数据库, 为花距的系统研究提供基础数据; (2)通过基因工程等方法构建花距突变体库, 进一步验证花距变异对物种多样性的贡献; (3)使用多组学的方法, 深入开展花距形成和发育分子机制的研究。

关键词: 花距, 关键创新, 传粉, 花距发育, 分子机制

Abstract

Background & AimThe floral spur stands out as a key innovative trait that has evolved in response to the interaction between plants and pollinators. This trait is widely distributed in angiosperms, showcasing a highly variable morphology among different species. Previous research has focused on exploring the complex relationship between floral spur and their corresponding pollinators.

ProgressFirstly, this review introduces the concept and function of the spur, elucidating the diversity in spur morphology, length, color, and contents of across various species; secondly, it describes the factors contributing to intraspecific and interspecific variations in floral spur morphology; then, it summarizes a series information on cellular and key molecular mechanisms governing the formation and development of floral spur. The distribution of the spur in angiosperms, coupled with the diversity in spur formation sites and the molecular mechanisms of development, suggests that the multiple origins of the spur with convergent evolutionary features, but the pattern of floral spur formation and development appears non-conserved in the evolutionary progression.

Prospects This review offers the following perspectives for future research on floral spur: (1) Constructing a comprehensive database documenting the phenotypes of angiosperm floral spurs to provide fundamental data for the systematic investigations; (2) Constructing a mutant library of floral spur through genetic engineering and other tools to further verify the contribution of floral spur variants to species diversity; (3) Investigating the molecular mechanisms of the formation and development of floral spur using a multi-omics approach.

Key words: floral spur, key innovation, pollination, floral spur development, molecular mechanisms

罗韶凡, 蒋凯, 黄卫昌 (2023) 植物花距表型趋同进化和发育机制多样化的研究进展. 生物多样性, 31, 23249. DOI: 10.17520/biods.2023249.

Shaofan Luo, Kai Jiang, Weichang Huang (2023) Advances in the convergent evolution of phenotypes and diversification of developmental mechanisms of floral spurs. Biodiversity Science, 31, 23249. DOI: 10.17520/biods.2023249.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2023249

https://www.biodiversity-science.net/CN/Y2023/V31/I11/23249

图/表 3

图1 有距植物在被子植物中的分布(参考APG IV分类系统以及毛茛目和唇形目内的系统发育关系, Hoot et al, 2015; The Angiosperm Phylogeny Group, 2016; Liu et al, 2020)。支长不代表真实时间尺度, 仅为美观考虑。A: 彗星兰; B: 距花万寿竹; C: 砂贝母; D: 紫堇; E: 淫羊藿; F: 加拿大耧斗菜; G: 紫花地丁; H: 距瓣豆; I: 矮小萼囊花; J: 萼距花; K: 旱金莲; L: 小萼凤仙花; M: 花锚; N: 蔓柳穿鱼; O: 心形双距花; P: 爱丝捕虫堇; Q: 露滴草; R: 角花; S: 长距忍冬; T: 半边莲; U: 奇异金鸾花。

Fig. 1 Distribution of plants with floral spur in the phylogenetic tree of angiosperms (Reference to the APG IV classification system and phylogenetic relationships within Ranunculales and Lamiales). Clade lengths do not represent true time scales only for aesthetic reasons. A, Angraecum eburneum; B, Disporum calcaratum; C, Fritillaria karelinii; D, Corydalis edulis; E, Epimedium brevicornu; F, Aquilegia canadensis; G, Viola philippica; H, Centrosema pubescens; I, Vochysia pygmaea; J, Cuphea hookeriana; K, Tropaeolum majus; L, Impatiens parvisepala; M, Halenia corniculata; N, Cymbalaria muralis; O, Diascia cordata; P, Pinguicula esseriana; Q, Sesamothamnus lugardi; R, Platostoma calcaratum; S, Lonicera calcarata; T, Heterotoma lobelioides; U, Goodenia paradoxa.

图2 190种彗星兰亚族物种对应的距长分布图。A-C分别表示3种彗星兰传粉者。A: Angraecum cadetii的传粉者Glomeremus sp. (Micheneau et al, 2010); B: A. bracteosum的传粉者Zosterops olivaceus (Micheneau et al, 2008), C: A. sesquipedale的传粉者Xanthopan praedicta (Minet et al, 2021)。红色字体表示该传粉者口器或头部长度, 绿色字体表示对应的植物距长。

Fig. 2 Bar plot of the corresponding floral spur lengths for 190 species of the Angraecinae. A-C indicate the pollinators of three Angraecum species, respectively. A, Glomeremus sp., pollinator of Angraecum cadetii (Micheneau et al, 2010); B, Zosterops olivaceus, pollinator of A. bracteosum (Micheneau et al, 2008), and C, Xanthopan praedicta, pollinator of A. sesquipedale (Minet et al, 2021). The red font indicates the length of arthropod mouthparts or head of that pollinator, and green font indicates the corresponding floral spur length.

表1 花距形成和发育过程中关键调控基因

Table 1 Key regulatory genes in floral spur formation and development

物种 Species	基因名称 Gene name	所属基因家族 Gene family	功能 Function	参考文献 Reference
金鱼草 Antirrhinum majus	AmHirz AmIna	KNOTTED 1-like homeobox (KNOX)	在花瓣管处分化出类似距的结构 Spur-like structures outgrowth from the petal tube	Golz et al, 2002
柳穿鱼 Linaria vulgaris	LvHirz LvIna	KNOTTED 1-like homeobox (KNOX)	在转基因烟草的花瓣上诱导出类似距的结构 Induced spur-like structures on the petals of transgenic tobacco	Box et al, 2011
耧斗菜 Aquilegia spp.	AqTCP4	TEOSINTE BRANCHED1/ CYCLOIDEA/PCF (TCP)	抑制距的细胞增殖 Restraining cell proliferation in spur	Yant et al, 2015
	POPOVICH (POP)	C2H2 zinc-finger	调控距早期发育的细胞增殖的过程, 同时对蜜腺的发育也起关键作用 Regulating the process of cell proliferation in early development and also plays a key role in the development of the nectaries	Ballerini et al, 2020
	ARF6/8	AUXIN RESPONSE FACTOR (ARF)	控制距表皮细胞各向异性生长 Regulating anisotropic growth of the spur epidermal cells	Zhang et al, 2020
	STY	STYLISH (SHORT INTERNODES/STY)	控制距内蜜腺发育 Controlling of nectary development within the spur	Min et al, 2019
	AqBEH1 AqBEH3 AqBEH4	BRI1-EMS-SUPRESSOR1 (BES1) / BRASSINAZOLE-RESISTANT1 (BRZ1)	控制距表皮细胞各向异性伸长 Regulating anisotropic growth of the spur epidermal cells	Conway et al, 2021

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