Saco Amaro, Rey-Campos Magalí, Gallardo-Escárate Cristian, Gerdol Marco, Novoa Beatriz, Figueras Antonio
Institute of Marine Research, Spanish National Research Council, Vigo, Spain.
Center for Aquaculture Research, University of Concepción, Concepción, Chile.
iScience. 2023 Sep 4;26(10):107827. doi: 10.1016/j.isci.2023.107827. eCollection 2023 Oct 20.
Presence/absence variation (PAV) is a well-known phenomenon in prokaryotes that was described for the first time in bivalves in 2020 in . The objective of the present study was to further our understanding of the PAV phenomenon in mussel biology. The distribution of PAV was studied in a mussel chromosome-level genome assembly, revealing a widespread distribution but with hotspots of dispensability. Special attention was given to the effect of PAV in gene expression, since dispensable genes were found to be inherently subject to distortions due to their sparse distribution among individuals. Furthermore, the high expression and strong tissue specificity of some dispensable genes, such as myticins, strongly supported their biological relevance. The significant differences in the repertoire of dispensable genes associated with two geographically distinct populations suggest that PAV is involved in local adaptation. Overall, the PAV phenomenon would provide a key selective advantage at the population level.
存在/缺失变异（PAV）是原核生物中一种广为人知的现象，2020年首次在双壳贝类中被描述。本研究的目的是进一步了解贻贝生物学中的PAV现象。在贻贝染色体水平的基因组组装中研究了PAV的分布，揭示了其广泛分布但存在可缺失热点。特别关注了PAV对基因表达的影响，因为发现可缺失基因由于在个体间分布稀疏而固有地容易受到扭曲。此外，一些可缺失基因，如贻贝抗菌肽，的高表达和强组织特异性有力地支持了它们的生物学相关性。与两个地理上不同的种群相关的可缺失基因库中的显著差异表明PAV参与了局部适应。总体而言，PAV现象将在种群水平上提供关键的选择优势。
