Perspective: 50 years of plant chromosome biology

Abstract

The past 50 years has been the greatest era of plant science discovery, and most of the discoveries have emerged from or been facilitated by our knowledge of plant chromosomes. At last we have descriptive and mechanistic outlines of the information in chromosomes that programs plant life. We had almost no such information 50 years ago when few had isolated DNA from any plant species. The important features of genes have been revealed through whole genome comparative genomics and testing of variants using transgenesis. Progress has been enabled by the development of technologies that had to be invented and then become widely available. Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) have played extraordinary roles as model species. Unexpected evolutionary dramas were uncovered when learning that chromosomes have to manage constantly the vast numbers of potentially mutagenic families of transposons and other repeated sequences. The chromatin-based transcriptional and epigenetic mechanisms that co-evolved to manage the evolutionary drama as well as gene expression and 3-D nuclear architecture have been elucidated these past 20 years. This perspective traces some of the major developments with which I have become particularly familiar while seeking ways to improve crop plants. I draw some conclusions from this look-back over 50 years during which the scientific community has (i) exposed how chromosomes guard, readout, control, recombine, and transmit information that programs plant species, large and small, weed and crop, and (ii) modified the information in chromosomes for the purposes of genetic, physiological, and developmental analyses and plant improvement.

Identification and Expression Profile of NCED Genes in Arachis hypogaea L. during Drought Stress

“…Tandem repeat gene duplication occurs in Arachis hypogaea. Gene replication refers to a gene duplicating in the genome, which can occur through various mechanisms such as haploid genome polyploidisation, chromosome recombination, and gene transposition [33,34]. This process enhances genome diversity and complexity, providing resources for gene evolution [35,36].…”

A karyomorphological comparison of seven species of Achillea L. from Kurdistan of Iran

“…Karyotype, the highest level of functional and structural organization of nuclear genome, that is essential for studying chromosomal characterization of plant species (Altınordu et al 2016). Comparative chromosomal taxon has been providing useful knowledge about patterns and evolutionary mechanisms in speciation (Flavell 2021). Chromosomal features, such as chromosome length, centromere index, number of chromosomes are crucial variables for investigating interrelationships and intrarelationships of taxa.…”