Genetic and epigenetic stability in Cannabis sativa mother plants

大麻母株的遗传和表观遗传稳定性

• 批准号: 555969-2020
• 负责人: Jones, AndrewMP
• 金额: $ 3.86万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=763533
• 关键词: Genetic; epigenetic; stability; Cannabis; sativa

Medicinal and recreational Cannabis has become a mult-billion dollar industry in Canada and is rapidly expanding around the world. Due to the variability among seedlings and Health Canada's stringent requirements, Cannabis is propagated using clonal means to produce uniform plants and products. This requires mother plants to be maintained indefinitely as a source of propagation material. A commonly observed phenomenon is that cuttings taken from a mother plan change over time, generally becoming less vigorous with lower levels of cannabinoids. These changes lead to lower productivity and batch to batch variability. The objective of this proposal is to investigate two potential mechanisms for this and develop best practices to prevent or remediate the decline. The first potential mechanism that will be investigated is genetic drift due to the accumulation of somatic mutations. To investigate this, samples from various parts of the plant will be sequenced to quantify the mutation rate. If mutations are found to accumulate, plants will be propagated from different regions of the plant (bottom vs top) over multiple cycles to compare genetic fidelity. This experiment will help to determine the rate of genetic drift in Cannabis and establish best practices to minimize it. The second potential mechanism that will be investigated is epigenetic changes due to loss of juvinility. To test this, cuttings will be taken from the bottom (more juvinile) and top (more mature) portion of the plant over several cycles. These cuttings will be evaluated for morphological juvinility traits. Transcriptome and DNA methylation will be evaluated to determine the cause of any differences. Additionally, plants produced through tissue culture, which is generally known to re-juvinate plants, will be compared to stem cuttings in the same manner. This part of the project will determine if epigenetic changes are contributing to the observed changes and develop approaches to minimize the decline. Overall, this project will help to identify the mechanism underlying and establish approaches to prevent or reverse the decline in plant quality that has been observed.

药用和娱乐大麻已成为加拿大数十亿美元的产业，并在世界各地迅速扩张。 由于幼苗之间的变异性和加拿大卫生部的严格要求，大麻采用克隆方式繁殖，以生产统一的植物和产品。 这需要无限期地保持母株作为繁殖材料的来源。 一个常见的现象是，从母计划中取出的插条会随着时间的推移而变化，通常会随着大麻素水平的降低而变得不那么活跃。 这些变化导致生产率降低和批次之间的差异性。 本提案的目的是调查这方面的两个潜在机制，并制定最佳做法，以防止或补救下降。 将被研究的第一个潜在机制是由于体细胞突变的积累而引起的遗传漂变。 为了调查这一点，将对来自植物不同部位的样本进行测序，以量化突变率。 如果发现突变累积，将在多个循环中从植物的不同区域（底部与顶部）繁殖植物，以比较遗传保真度。 这项实验将有助于确定大麻的遗传漂变率，并建立最佳做法，以尽量减少它。第二个潜在的机制，将被调查是表观遗传变化，由于损失的juvinility。 为了测试这一点，将在几个周期内从植物的底部（更幼）和顶部（更成熟）部分采集插条。 这些插枝将进行形态幼态性状评价。 将评价转录组和DNA甲基化，以确定任何差异的原因。 此外，通过组织培养产生的植物（通常已知其使植物再幼化）将以相同的方式与茎插条进行比较。 该项目的这一部分将确定表观遗传变化是否有助于观察到的变化，并开发方法以尽量减少下降。 总的来说，该项目将有助于确定潜在的机制，并建立方法，以防止或扭转已观察到的植物质量下降。