Identification and characterization of microRNAs expressed in antennae of Holotrichia parallela Motschulsky and their possible roles in olfactory regulation

Abstract

MicroRNAs (miRNAs) are small noncoding RNAs that play posttranscriptional, regulatory roles in various biological processes. However, there has been limited investigation into the potential function of miRNAs in olfaction. The coleopteran Holotrichia parallela is an economically important pest, and miRNAs have been identified in only one coleopteran (Tribolium castaneum). Therefore, this study was conducted to identify miRNAs expressed in the antennae of H. parallela and obtain insights into their possible roles in olfaction. By combining deep sequencing and miRDeep2 software, a total of 99 miRNAs, including 76 conserved miRNAs and 23 novel miRNAs, were identified from H. parallela antennae. The 76 conserved miRNAs belong to 63 families and the other 23 may be species specific or tissue specific. The identified miRNAs have many conserved features of miRNAs. Evaluation of the conservation of the identified miRNA families across different species revealed that most of the families are insect specific. The prediction and annotation of targets suggested that 13 of the identified miRNAs participate in olfactory regulation. Gender differences in antennal expression of nine of the olfactory-related miRNAs were confirmed by quantitative real-time PCR.

Characterization and target gene analysis of microRNAs in the antennae of the parasitoid wasp Microplitis mediator

“…This fits the characteristics of animal small RNAs and confirms the reliability of using M. demolitor genome data as a reference. Previously, in the antennae of the beetle Holotrichia parallela , 99 miRNAs were identified, including 76 known miRNAs and 23 novel miRNAs (Wang et al ., 2017a). Moreover, in the head of the hymenopteran bumblebee, 364 known and 89 novel miRNAs were identified (Liu et al ., 2019).…”

“…Here, we identified 296 known miRNAs and 46 novel miRNAs in the antennae of M. mediator . The lengths and base distribution of these miRNAs are consistent with those of other insect species (Sun et al ., 2015; Guo et al ., 2016; Wang et al ., 2017a; Liu et al ., 2019).…”

“…The sensitive olfactory systems of parasitoid wasps play an important role in host location. In our previous work, we identified large sets of chemosensory genes, including 169 odorant receptors (ORs), 17 ionotropic receptors (IRs), two gustatory receptors (GRs), two SNMPs, 20 OBPs, three chemosensory proteins (CSPs) and two Niemann‐Pick type C2 proteins in the antennae of M. mediator , and a number of specific and olfactory‐associated proteins have been functionally characterized in this wasp (Zhang et al ., 2009, 2011; Li et al ., 2014; Ma et al ., 2014; Wang et al ., 2015, 2016a, 2017b, 2018; Peng et al ., 2017; Zheng et al ., 2018; Shan et al ., 2019a,b). Nonetheless, little is known about the roles of miRNAs in chemoreception in M. mediator and other hymenopteran wasps.…”

“…Moreover, some miRNAs expressed in the antennae of the dark black chafer ( Holotrichia parallela ) are predicted to target chemosensory‐related genes, such as odorant binding proteins (OBPs) and sensory neuron membrane proteins (SNMPs). It was thus proposed that these miRNAs may play a role in olfactory regulation (Ju et al ., 2014; Wang et al ., 2017a).…”

Identification and tissue expression profiling of candidate UDP-glycosyltransferase genes expressed in Holotrichia parallela motschulsky antennae

“…Insect and tissue collection H. parallela strains used in this study were collected in Cangzhou, China. The antennae, heads, thoraces, abdomens, legs, and wings of male and female adults were dissected and promptly immersed in liquid nitrogen and stored at −80°C until use (Wang et al, 2017).…”