Integration of Physical, Genetic, and Cytogenetic Mapping Data for Cellulose Synthase (CesA) Genes in Flax (Linum usitatissimum L.).

Olga Y Yurkevich,Nadezhda L Bolsheva,Ilya V Kirov,Marina V Bogdanova,Svyatoslav A Zoschuk,Zoya E Grushetskaya,Olga V Muravenko,Olga A Rachinskaya,Valentina A Lemesh,Tatiana E Samatadze,Alexandra V Amosova

doi:10.3389/fpls.2017.01467

Abstract

Flax, Linum usitatissimum L., is a valuable multi-purpose plant, and currently, its genome is being extensively investigated. Nevertheless, mapping of genes in flax genome is still remaining a challenging task. The cellulose synthase (CesA) multigene family involving in the process of cellulose synthesis is especially important for metabolism of this fiber crop. For the first time, fluorescent in situ hybridization (FISH)-based chromosomal localization of the CesA conserved fragment (KF011584.1), 5S, and 26S rRNA genes was performed in landrace, oilseed, and fiber varieties of L. usitatissimum. Intraspecific polymorphism in chromosomal distribution of KF011584.1 and 5S DNA loci was revealed, and the generalized chromosome ideogram was constructed. Using BLAST analysis, available data on physical/genetic mapping and also whole-genome sequencing of flax, localization of KF011584.1, 45S, and 5S rRNA sequences on genomic scaffolds, and their anchoring to the genetic map were conducted. The alignment of the results of FISH and BLAST analyses indicated that KF011584.1 fragment revealed on chromosome 3 could be anchored to linkage group (LG) 11. The common LG for 45S and 5S rDNA was not found probably due to the polymorphic localization of 5S rDNA on chromosome 1. Our findings indicate the complexity of integration of physical, genetic, and cytogenetic mapping data for multicopy gene families in plants. Nevertheless, the obtained results can be useful for future progress in constructing of integrated physical/genetic/cytological maps in L. usitatissimum which are essential for flax breeding.

Highlights

Cultivated flax (Linum usitatissimum L., 2n = 2x = 30) is an annual self-pollinated crop widely grown for use in food production, industry, and medicine
The cellulose synthase (CesA) multigene family encoding the glycosyltransferase enzymes plays a key role in the process of plant cellulose synthesis
These genes are especially important for bast fiber crops such as flax (L. usitatissimum) as the metabolism of fibers cells is oriented toward the extensive cellulose synthesis (Gorshkova et al, 2005; Chantreau et al, 2015)

Summary

Introduction

According to the linkage groups (LGs), consensus genetic and physical maps of flax were created (Cloutier et al, 2012; Kumar et al, 2015) This map has not been correlated to flax cytogenetic mapping developed earlier (Muravenko et al, 2003, 2009; Rachinskaya et al, 2011), and chromosomal localization of individual genes is still unexplored. Among all methods of physical mapping, only molecular cytogenetic techniques, such as fluorescent in situ hybridization (FISH), allow specific DNA sequences to be directly localized on mitotic and meiotic chromosomes. In this context, it can help their association with the LGs of genetic maps. Highly conserved genes are usually mapped, and among these are cellulose synthase (CesA) genes of plants

Methods

Results

Conclusion