Chromosome level genomic release of capers (mouse melon).

Capparis spinosa is a perennial vine semi-shrub, a Capparidaceae plant of the genus Capparis, which originated in the arid regions of West or Central Asia and is mainly distributed in Xinjiang, Tibet, Gansu and other places
in China.
Capers have the characteristics of strong drought resistance, wind and sand resistance, barren resistance and high temperature resistance, and are mainly used as medicinal plants and sand control plants
in China.
Its chemical composition is complex, with antioxidant, antibacterial, anticancer, liver protection and other pharmacological effects, folk used in the treatment of arthritis, frozen shoulder, etc
.
Capers are also widely distributed in the European Mediterranean region and are very popular in places such as Cyprus, Malta and Italy, where their fruits are marinated in salt water or vinegar and often used as an appetizer and the bud part is often used as a seasoning
.

Recently, the team of researcher Tian Changyan of the Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, together with the team of the Bioinformatics Center of the Cotton Research Institute of the Chinese Academy of Agricultural Sciences, completed the first chromosome-level high-quality caper reference genome
.
The caper genome is about 274.
53 MB, of which 99.
23% of the sequence is anchored on 21 chromosomes, with a contig N50 of 9.
36 MB and a scaffold N50 of 15.
15 MB
.
Based on homologous sequence alignment, de novo prediction, and transcriptome evidence supporting annotation of the caper genome, a total of 21,577 protein-coding genes
were obtained.

This study revealed the evolutionary characteristics of capers, identified terpenoid-related genes and heat shock protein (HSP)-related genes during the growth process of capers, and provided an important reference
for the research on the regulatory mechanism of key medicinal components and drought and high temperature resistance of capers.
As the first chromosome-level reference genome of the family Mandarinidae, the release of the caper genome provides valuable genetic information for the subsequent comprehensive development and utilization, and also lays a solid foundation
for the follow-up research of the entire Mandarin family.

The results of the study were concluded in "The Capparis spinosa var.
Herbacea genome provides the first genomic instrument for a diversity and evolution study of the Capparaceae family"
.
The research was supported
by the National Key R&D Program and the pilot project of the Chinese Academy of Sciences.

Article link: https://doi.
org/10.
1093/gigascience/giac106

Fig.
1 Epitype photo of capers (A) Adult caper plants; (B) flowers; (C) fruits; (D) stem; (E) Leaf tip

(Photo by Hou Yiguo)

Figure 2.
Chromosome-level genomic and collinearity analysis of capers