Synthetic minichromosomes in plants: past, present, and promise

• Published in: The Plant journal : for cell and molecular biology 2024-12, Vol.120 (6), p.2356-2366
• Main Authors: Birchler, James A., Kelly, Jacob, Singh, Jasnoor, Liu, Hua, Zhang, Zhengzhi, Char, Si Nian, Sharma, Malika, Yang, Hua, Albert, Patrice S., Yang, Bing
• Format: Article
• Language: English
• Subjects: Artificial chromosomes; B chromosomes; Centromere - genetics; Centromeres; Chromosomes; Chromosomes, Artificial - genetics; Chromosomes, Plant - genetics; CRISPR; CRISPR-Cas Systems; CRISPR‐Cas9; engineered minichromosomes; Epigenetics; gene editing; Gene Editing - methods; Genes; genetic engineering; Genetic Engineering - methods; haploids; Plant cells; Plant layout; Plants - genetics; Plants, Genetically Modified; Reintroduction; site‐specific recombinases; synthetic chromosomes; Telomere - genetics; Telomeres
• ISSN: 0960-7412; 1365-313X; 1365-313X
• DOI: 10.1111/tpj.17142

SUMMARY The status of engineered mini‐chromosomes/artificial chromosomes/synthetic chromosomes in plants is summarized. Their promise is that they provide a means to accumulate foreign genes on an independent entity other than the normal chromosomes, which would facilitate stacking of novel traits in a way that would not be linked to endogenous genes and that would facilitate transfer between lines. Centromeres in plants are epigenetic, and therefore the isolation of DNA underlying centromeres and reintroduction into plant cells will not establish a functional kinetochore, which obviates this approach for in vitro assembly of plant artificial chromosomes. This issue was bypassed by using telomere‐mediated chromosomal truncation to produce mini‐chromosomes with little more than an endogenous centromere that could in turn be used as a foundation to build synthetic chromosomes. Site‐specific recombinases and various iterations of CRISPR‐Cas9 editing provide many tools for the development and re‐engineering of synthetic chromosomes. Significant Statement With increasing interest in synthetic biology in plants, approaches for producing synthetic chromosomes are needed. The status of engineered minichromosomes is reviewed and future directions and potential applications are discussed.