Mogro Ezequiel G, Draghi Walter O, Lagares Antonio, Lozano Mauricio J
Instituto de Biotecnología y Biología Molecular (IBBM), Dep. Ciencias Biológicas - Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CONICET CCT-LaPlata. La Plata, Buenos Aires, Argentina.
Mob DNA. 2024 Sep 5;15(1):17. doi: 10.1186/s13100-024-00327-8.
Rhizobia are alpha- and beta- Proteobacteria that, through the establishment of symbiotic interactions with leguminous plants, are able to fix atmospheric nitrogen as ammonium. The successful establishment of a symbiotic interaction is highly dependent on the availability of nitrogen sources in the soil, and on the specific rhizobia strain. Insertion sequences (ISs) are simple transposable genetic elements that can move to different locations within the host genome and are known to play an important evolutionary role, contributing to genome plasticity by acting as recombination hot-spots, and disrupting coding and regulatory sequences. Disruption of coding sequences may have occurred either in a common ancestor of the species or more recently. By means of ISComapare, we identified Differentially Located ISs (DLISs) in nearly related rhizobial strains of the genera Bradyrhizobium, Mesorhizobium, Rhizobium and Sinorhizobium. Our results revealed that recent IS transposition could have a role in adaptation by enabling the activation and inactivation of genes that could dynamically affect the competition and survival of rhizobia in the rhizosphere.
根瘤菌属于α-和β-变形菌纲，通过与豆科植物建立共生关系，能够将大气中的氮固定为铵态氮。共生关系的成功建立高度依赖于土壤中氮源的可用性以及特定的根瘤菌菌株。插入序列（ISs）是简单的可移动遗传元件，可移动到宿主基因组内的不同位置，已知其在进化中发挥重要作用，通过作为重组热点促进基因组可塑性，并破坏编码和调控序列。编码序列的破坏可能发生在该物种的共同祖先中，也可能是最近才发生的。通过ISComapare，我们在慢生根瘤菌属、中生根瘤菌属、根瘤菌属和中华根瘤菌属的近缘根瘤菌菌株中鉴定出差异定位的插入序列（DLISs）。我们的结果表明，近期的IS转座可能通过激活和失活那些能够动态影响根瘤菌在根际的竞争和生存的基因，从而在适应过程中发挥作用。
