Molecular cytogenetic map visualizes the heterozygotic genome and identifies translocation chromosomes in Citrus sinensis.

Citrus sinensis is the most cultivated and economically valuable Citrus species in the world, whose genome has been assembled by three generation sequencings. However, chromosome recognition remains a problem due to the small size of chromosomes, and difficulty in differentiating between pseudo and real chromosomes because of a highly heterozygous genome. Here, we employ fluorescence in situ hybridization (FISH) with 9 chromosome painting probes, 30 oligo pools, and 8 repetitive sequences to visualize 18 chromosomes.

Localization and characterization of Citrus centromeres by combining half-tetrad analysis and CenH3-associated sequence profiling.

The physical locations of citrus centromere are revealed by combining genetic and immunological assays for the first time and nine citrus centromere-specific markers for cytogenetics are mined. Centromere localization is challenging, because highly redundant repetitive sequences in centromeric regions make sequence assembly difficult. Although several citrus genomes have been released, the centromeric regions and their characteristics remain to be elucidated.

Genome-wide identification, characterization, interaction network and expression profile of gene family in sweet orange ().

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key glycolytic enzyme that plays important roles in multiple cellular processes including phytohormone signaling, plant development, and transcriptional regulation. Although genes have been well characterized in various plant species such as , tobacco, wheat, rice, and watermelon, comprehensive analysis has yet to be completed at the whole genome level in sweet orange (). In this study, six genes distributed across four chromosomes were identified within the sweet orange genome.