Webster Cynthia, Figueroa-Corona Laura, Méndez-González Iván David, Álvarez-Soto Lluvia, Neale David B, Jaramillo-Correa Juan Pablo, Wegrzyn Jill L, Vázquez-Lobo Alejandra
Department of Ecology and Evolutionary Biology University of Connecticut Storrs Connecticut USA.
Departamento de Ecología Evolutiva Instituto de Ecología Universidad Nacional Autónoma de México Ciudad de México Mexico.
Ecol Evol. 2022 Feb 16;12(2):e8611. doi: 10.1002/ece3.8611. eCollection 2022 Feb.
In land plants, heteroblasty broadly refers to a drastic change in morphology during growth through ontogeny. and are conifers of independent lineages known to exhibit leaf heteroblasty between the juvenile and adult life stage of development. Juvenile leaves of develop spirally on the main stem and appear decurrent, flattened, and needle-like; whereas adult photosynthetic leaves are triangular or semi-circular needle-like, and grow in whorls on secondary or tertiary compact dwarf shoots. By comparison, juvenile leaves are decurrent and needle-like, and adult leaves are compact, short, and scale-like. Comparative analyses were performed to evaluate differences in anatomy and gene expression patterns between developmental phases in both species. RNA from 12 samples was sequenced and analyzed with available software. They were assembled de novo from the RNA-Seq reads. Following assembly, 63,741 high-quality transcripts were functionally annotated in and 69,448 in . Evaluation of the orthologous groups yielded 4140 shared gene families among the four references (adult and juvenile from each species). Activities related to cell division and development were more abundant in juveniles than adults in , and more abundant in adults than juveniles in . Overall, there were 509 up-regulated and 81 down-regulated genes in the juvenile condition of and 14 up-regulated and 22 down-regulated genes in . Gene interaction network analysis showed evidence of co-expression and co-localization of up-regulated genes involved in cell wall and cuticle formation, development, and phenylpropanoid pathway, in juvenile leaves. Whereas in , differential expression and gene interaction patterns were detected in genes involved in photosynthesis and chloroplast biogenesis. Although and both exhibit leaf heteroblastic development, little overlap was detected, and unique genes and pathways were highlighted in this study.
在陆生植物中，异时性大致指个体发育过程中生长期间形态的急剧变化。[两种植物名称未给出，分别用“和”指代]是独立谱系的针叶树，已知在发育的幼年和成年阶段表现出叶片异时性。[第一种植物名称未给出，用“”指代]的幼叶在主茎上呈螺旋状生长，看起来下延、扁平且呈针状；而成年光合叶呈三角形或半圆形针状，在次生或三生紧密矮枝上呈轮状生长。相比之下，[第二种植物名称未给出，用“”指代]的幼叶下延且呈针状，成年叶紧密、短小且呈鳞片状。进行了比较分析以评估两个物种发育阶段之间在解剖结构和基因表达模式上的差异。对12个样本的RNA进行了测序，并使用可用软件进行分析。它们从RNA测序读数中进行了从头组装。组装后，[第一种植物名称未给出，用“”指代]中有63741个高质量转录本得到功能注释，[第二种植物名称未给出，用“”指代]中有69448个。对直系同源组的评估在四个参考样本（每个物种的成年和幼年样本）中产生了4140个共享基因家族。在[第一种植物名称未给出，用“”指代]中，与细胞分裂和发育相关的活动在幼体中比成体中更丰富，而在[第二种植物名称未给出，用“”指代]中在成体中比幼体中更丰富。总体而言，[第一种植物名称未给出，用“”指代]幼年期有509个上调基因和81个下调基因，[第二种植物名称未给出，用“”指代]中有14个上调基因和22个下调基因。基因相互作用网络分析显示，在[第一种植物名称未给出，用“”指代]幼叶中，参与细胞壁和角质层形成、发育以及苯丙烷途径的上调基因存在共表达和共定位的证据。而在[第二种植物名称未给出，用“”指代]中，在参与光合作用和叶绿体生物发生的基因中检测到差异表达和基因相互作用模式。尽管[两种植物名称未给出，分别用“和”指代]都表现出叶片异时性发育，但检测到的重叠很少，并且本研究突出了独特的基因和途径。
