Joseph Gottlieb Kölreuter Institute for Plant Sciences (JKIP) - Molecular Biology, Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany.
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, 06466, Seeland, Germany.
New Phytol. 2024 Jan;241(2):541-552. doi: 10.1111/nph.19414. Epub 2023 Nov 20.
Spontaneous chromosomal rearrangements (CRs) play an essential role in speciation, genome evolution and crop domestication. To be able to use the potential of CRs for breeding, plant chromosome engineering was initiated by fragmenting chromosomes by X-ray irradiation. With the rise of the CRISPR/Cas system, it became possible to induce double-strand breaks (DSBs) in a highly efficient manner at will at any chromosomal position. This has enabled a completely new level of predesigned chromosome engineering. The genetic linkage between specific genes can be broken by inducing chromosomal translocations. Natural inversions, which suppress genetic exchange, can be reverted for breeding. In addition, various approaches for constructing minichromosomes by downsizing regular standard A or supernumerary B chromosomes, which could serve as future vectors in plant biotechnology, have been developed. Recently, a functional synthetic centromere could be constructed. Also, different ways of genome haploidization have been set up, some based on centromere manipulations. In the future, we expect to see even more complex rearrangements, which can be combined with previously developed engineering technologies such as recombinases. Chromosome engineering might help to redefine genetic linkage groups, change the number of chromosomes, stack beneficial genes on mini cargo chromosomes, or set up genetic isolation to avoid outcrossing.
自发染色体重排（CRs）在物种形成、基因组进化和作物驯化中发挥着重要作用。为了能够利用 CRs 的潜力进行育种，人们通过 X 射线照射来使染色体碎片化，从而启动了植物染色体工程。随着 CRISPR/Cas 系统的兴起，现在可以在任何染色体位置以极高的效率随意诱导双链断裂（DSBs）。这使预定的染色体工程达到了全新的水平。通过诱导染色体易位，可以打破特定基因之间的遗传连锁。为了进行育种，可以反转抑制遗传交换的自然倒位。此外，还开发了多种通过减小常规标准 A 或额外 B 染色体的大小来构建小型染色体的方法，这些染色体可以作为未来植物生物技术中的载体。最近，还构建了一个功能性的合成着丝粒。此外，还建立了不同的基因组单倍体化方法，其中一些方法基于着丝粒的操作。未来，我们预计会看到更复杂的重排，这些重排可以与以前开发的工程技术（如重组酶）结合使用。染色体工程可能有助于重新定义遗传连锁群，改变染色体的数量，将有益基因堆叠在小型载体染色体上，或建立遗传隔离以避免杂交。
