Dissecting cricket genomes for the advancement of entomology and entomophagy

Abstract

Significant advances in biophysical methods such as next-generation sequencing technologies have now opened the way to conduct evolutionary and applied research based on the genomic information of greatly diverse insects. Crickets belonging to Orthoptera (Insecta: Polyneoptera), one of the most flourishing groups of insects, have contributed to the development of multiple scientific fields including developmental biology and neuroscience and have been attractive targets in evolutionary ecology for their diverse ecological niches. In addition, crickets have recently gained recognition as food and feed. However, the genomic information underlying their biological basis and application research toward breeding is currently underrepresented. In this review, we summarize the progress of genomics of crickets. First, we outline the phylogenetic position of crickets in insects and then introduce recent studies on cricket genomics and transcriptomics in a variety of fields. Furthermore, we present findings from our analysis of polyneopteran genomes, with a particular focus on their large genome sizes, chromosome number, and repetitive sequences. Finally, how the cricket genome can be beneficial to the food industry is discussed. This review is expected to enhance greater recognition of how important the cricket genomes are to the multiple biological fields and how basic research based on cricket genome information can contribute to tackling global food security.

Genome and Genetic Engineering of the House Cricket (Acheta domesticus): A Resource for Sustainable Agriculture

“…A quick comparison of the length of the BUSCO reference gene sequences estimated that the A. domesticus genes were on average 80% longer than those in T castaneum. We also noticed that, in most cases, the longer genes were due to longer introns that may be due to TEs as has been observed in other Orthoptera [ 53 , 54 ]. Therefore, we compared repetitive elements in the A. domesticus genome assembly with those available for other orthopterans and found that the A. domesticus genome assembly contains the highest content of TEs (almost half of the assembly) compared to other cricket genomes.…”

“…Because repetitive elements, in particular transposable elements (TEs), are well-known contributors to genome size expansion in a wide range of insect species [ 53 , 54 ], we further examined the relative contribution of repetitive elements to the genome sizes of the orthopteran species. There was a significant correlation between total contents of repetitive elements and genome sizes in Orthoptera species ( p = 0.024 and R2 = 0.61) ( Figure S6a ).…”

Genome and Genetic Engineering of the House Cricket (Acheta domesticus): Applications for Sustainable Agriculture

“…A quick comparison of the length of the BUSCO reference gene sequences estimated that the A. domesticus genes were on average 80% longer than those in T castaneum. We also noticed that, in most cases, the longer genes were due to longer introns that may be due to TEs as has been observed in Orthoptera [72–73]. Therefore, we compared repetitive elements in the A. domesticus genome assembly with those available for other orthopterans and found that the A. domesticus genome assembly contains the highest content of TEs (almost half of the assembly) compared to other cricket genomes.…”

“…For example, in the cricket genomes, L. kohalensis LINE had the highest abundance at 13.4%, while G. bimaculatus and T. oceanicus had only 3.34% and 4.04% LINE, respectively. Because repetitive elements, in particular transposable elements (TEs), are well-known contributors to genome size expansion in a wide range of insect species [72][73], we further examined the relative contribution of repetitive elements to the genome sizes of the orthopteran species. There was a significant correlation between total contents of repetitive elements and genome sizes in Orthoptera species (P=0.024 and R 2 = 0.61) (Figure S6a).…”

“…A quick comparison of the length of the BUSCO reference gene sequences estimated that the A. domesticus genes were on average 80% longer than those in T castaneum. We also noticed that, in most cases, the longer genes were due to longer introns that may be due to TEs as has been observed in Orthoptera [72][73]. Therefore, we compared repetitive elements in the A.…”