Small RNA profiling of the whitefly, Bemisia tabaci MEAM1 in response to feeding on tomato infected with Tomato yellow leaf curl virus

Authors: Hasegawa, Daniel; Shamimuzzaman, Md - Shamim; CHEN, WENBO - Boyce Thompson Institute; Simmons, Alvin; FEI, ZHANGJUN - Boyce Thompson Institute; Ling, Kai-Shu

Submitted to: International Geminivirus Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 11/4/2019
Publication Date: N/A
Citation: N/A

Interpretive Summary: Begomoviruses are plant viruses that impact food and fiber crops globally, and are transmitted by the whitefly, Bemisia tabaci. Tomato yellow leaf curl virus (TYLCV) is a devastating whitefly-transmitted Begomovirus that affects tomato production in the U.S. and other parts of the world. Our previous studies highlighted how whitefly gene expression changes after feeding on tomato infected with TYLCV for 24, 48, and 72 hours. Here, using the same experimental material, we analyzed how whitefly small RNAs change during feeding on TYLCV-infected tomato. Small RNAs are non-coding regulatory elements commonly found in plants, animals and insects, and play an important role in regulating gene expression, transposable elements, and parasite immunity. Major classes of small RNAs include small interfering RNAs (siRNAs) and microRNAs (miRNAs), which are primarily involved in silencing gene expression, while PIWI-interacting RNAs (piRNAs) regulate the activity of transposable elements as well as silence the expression of protein coding genes. In this study, we found numerous miRNAs that are unique to whiteflies, and several piRNAs that are only activated or suppressed when whiteflies fed on TYLCV-infected tomato. These data suggest a role for small RNAs during whitefly feeding on tomato that is infected with TYLCV and provides further knowledge on whitefly-begomovirus interactions.

Technical Abstract: The whitefly, Bemisia tabaci MEAM1 is a notorious vector of viruses that impacts food and fiber production on a global scale. We previously characterized the transcriptomic response of whiteflies that fed on tomato infected with the Begomovirus, Tomato yellow leaf curl virus (TYLCV) after 24 h, 48 h, and 72 h. Using the same pools of RNA that were used in these experiments, we sought to characterize changes in whitefly small RNAs using a deep sequencing approach, with a specific focus on piwi-interacting RNAs (piRNAs) and micro-RNAs (miRNAs). Numerous miRNAs were found specific to whiteflies, while only several miRNAs were differentially expressed in whiteflies fed on TYLCV-infected tomato, compared with those fed on healthy tomato. Numerous piRNA clusters were induced and suppressed when whiteflies fed on TYLCV-infected tomato, and interestingly, six protein-coding genes were targeted in TYLCV-infected leaves. Although piRNAs primarily regulate the activity of transposable elements, these data suggest they may have additional functions in regulating protein coding genes during whitefly-virus interactions.