Chromosome Nomenclature and Cytological Characterization of Sacred Lotus

Abstract

Sacred lotus is a basal eudicot plant that has been cultivated in Asia for over 7,000 years for its agricultural, ornamental, religious, and medicinal importance. A notable characteristic of lotus is the seed longevity. Extensive endeavors have been devoted to dissect its genome assembly, including the variety China Antique, which germinated from a 1,300-year-old seed. Here, cytogenetic markers representing the 10 largest megascaffolds, which constitute approximately 70% of the lotus genome assembly, were developed. These 10 megascaffolds were then anchored to the corresponding lotus chromosomes by fluorescence in situ hybridization using these cytogenetic markers, and a set of chromosome-specific cytogenetic markers that could unambiguously identify each of the 8 chromosomes was generated. Karyotyping was conducted, and a nomenclature based on chromosomal length was established for the 8 chromosomes of China Antique. Comparative karyotyping revealed relatively conserved chromosomal structures between China Antique and 3 modern cultivars. Interestingly, significant variations in the copy number of 45S rDNA were detected between China Antique and modern cultivars. Our results provide a comprehensive view on the chromosomal structure of sacred lotus and will facilitate further studies and the genome assembly of lotus.

Identification of QTLs and Putative Candidate Gene Involved in Rhizome Enlargement of Asian lotus (Nelumbo Nucifera)

“…For megascaffolds 6, blocks 10A, 10C and 2E were reassembled as a new megascaffold (Figure S1). Similar results were also observed by uorescence in situ hybridization (FISH) analysis in lotus (Meng et al 2017). The FISH assay also revealed that megascaffolds 1-10 were assigned to eight chromosomes.…”

Benzylisoquinoline Alkaloids Biosynthesis in Sacred Lotus

“…Analysis of the Nelumbo nucifera genome sequence suggest that, after the lineage-specific whole-genome duplication event (approximately 18 to 76 million years ago), several rearrangements (i.e., ancestral chromosome fissions, fusions, and a single inversion) were responsible for the modern diploid karyotype (16 chromosomes) [ 67 , 68 ]. The sacred lotus genome is ~1 Gb in size and encodes approximately 27,000 genes [ 1 , 2 ].…”

Karyology of Some Coastal and Water Plants from Far East (Russia)

“…Many researchers suggest that N. komarovii is a Far Eastern race of N. nucifera Gaertn., widely used in medicine, and as a delicacy in Chinese and Japanese cuisine. Karyotype study revealed the same chromosome number (2n = 16) in N. nucifera (Diao et al 2005, 2006, 2011, Meng et al 2017, Ming et al 2013, Yang et al 1998. Our data on the morphology of N. komarovii chromosomes are confirmed by studies of Chinese scientists (Meng et al 2017).…”