Multiple neurons encode CrebB dependent appetitive long-term memory in the mushroom body circuit

Abstract

Lasting changes in gene expression are critical for the formation of long-term memories (LTMs), depending on the conserved CrebB transcriptional activator. While requirement of distinct neurons in defined circuits for different learning and memory phases have been studied in detail, only little is known regarding the gene regulatory changes that occur within these neurons. We here use the fruit fly as powerful model system to study the neural circuits of CrebB-dependent appetitive olfactory LTM. We edited the CrebB locus to create a GFP-tagged CrebB conditional knockout allele, allowing us to generate mutant, post-mitotic neurons with high spatial and temporal precision. Investigating CrebB-dependence within the mushroom body (MB) circuit we show that MB α/β and α’/β’ neurons as well as MBON α3, but not in dopaminergic neurons require CrebB for LTM. Thus, transcriptional memory traces occur in different neurons within the same neural circuit.

MAPK-directed activation of the whitefly transcription factor CREB leads to P450-mediated imidacloprid resistance

“…A further member of this superfamily, CREB, is involved in wide-ranging processes including glucose homeostasis, growth-factor-dependent cell survival, nervous system development, learning, memory, synaptic plasticity, and drug adaptive responses (16). In insects, CREB has also been shown to play a role in diverse processes including long-term memory formation, waking and rest homeostasis, starvation resistance, age-dependent labor division, and environmentinduced behavioral plasticity (17)(18)(19)(20)(21). However, the role of CREB in regulating detoxification enzymes in the context of insect resistance to insecticides has never been explored.…”

Identification ofFoxPcircuits involved in locomotion and object fixation inDrosophila

“…The insect mushroom-bodies (MBs) are not only known as a center for olfactory learning and memory (Dolan et al, 2018;Felsenberg et al, 2018;König et al, 2019;Lyutova et al, 2019;Thum and Gerber, 2019;Turrel et al, 2018;e.g., Warth Pérez Arias et al, 2020;Widmer et al, 2018), they are also involved in the temporal and spatial control of locomotor activity (Besson and Martin, 2005;Helfrich-Förster et al, 2002;Lark et al, 2017;Lebreton and Martin, 2009;Mabuchi et al, 2016;Manjila et al, 2019;e.g., Martin et al, 1998;Serway et al, 2009;Sun et al, 2018;Xiong et al, 2010). In addition, (Castells-Nobau et al, 2019) (Fig.…”

Initiated by CREB: Resolving Gene Regulatory Programs in Learning and Memory

“…Because only a few engram cells encode a memory, studying only a small population of cells will be beneficial for understanding the memory consolidation process. Recently, a conditional knockout line for CREB was established in the fly . To this end, the coding sequence of CREB was flanked by flippase recognition target (FRT) sites.…”

“…It was also shown that only a subset of MB neurons is required for LTM. Furthermore, the downstream neurons of these cells require CREB for LTM . Thus, this fly‐line allows the study of memory‐relevant cells in greater detail.…”

“…Epigenetic mechanisms such as DNA methylation and histone acetylation as well as the role of cofactors are gaining importance. Moreover, recent evidence suggests that CREB initiates a gene regulatory cascade, which appears to be critical for long‐lasting memories . Thus, CREB provides an early entry point and a critical link to a gene regulatory program in LTM.…”