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Conscious awareness to the events and stimuli around us is a central part of our everyday experience. Yet, are humans the only species that experiences conscious awareness? Since non-verbal species cannot report their internal states, philosophers and scientists have long debated whether the question of animal consciousness is empirically testable, and it still remains a topic of speculation (Dawkins, 2015; Gutfreund, 2017). In the large spectrum of views, some advocate that consciousness may require complex processes like language, a capacity that is unique to adult humans (Dennett, 1995) or a human-like theory of mind (Carruthers, 1998), which may extend to only a few selected species such as great apes (e.g., Krupenye, Kano, Hirata, Call, & Tomasello, 2016; but see Horschler, MacLean, & Santos, 2020). In contrast, others have used neuroanatomical similarities to argue that a number of species (including some birds and octopuses) are likely to be capable of generating conscious experience (see, for example, the Cambridge declaration on consciousness, 2012). Others argue that non-human animals are conscious on the basis of intelligent behaviors which, at least in humans, seem to coincide with conscious awareness as supporting evidence for animal consciousness. These include behaviors such as planning (Osvath & Osvath, 2008), or metacognition (Hampton, Engelberg, & Brady, 2020; Rosati & Santos, 2016), for review see Boly et al., 2013; Griffin & Speck, 2004. Yet, since many complex human behaviors and high-level functions can be performed outside of conscious awareness (i.e., Hassin, 2013), it is difficult to determine whether non-human animals that display intelligent behaviors are indeed conscious or not (Carruthers, 2018). Furthermore, given the ambiguity and difficulty in disentangling conscious from non-conscious processes in non-verbal species, many consider the question of animal consciousness as far from having been resolved (Dawkins, 2015; Gutfreund, 2017). For many, the gap in evidence needed to unambiguously infer animal consciousness is considered “as wide as ever” (Dawkins, 2012).

Gene expression can be regulated post-transcriptionally through dynamic and reversible RNA modifications. A recent noteworthy example is [N.sup.6]-methyladenosine ([m.sup.6]A), which affects messenger RNA (mRNA) localization, stability, translation and splicing. Here we report on a new mRNA modification, [N.sup.1]-methyladenosine ([m.sup.1]A), that occurs on thousands of different gene transcripts in eukaryotic cells, from yeast to mammals, at an estimated average transcript stoichiometry of 20% in humans. Employing newly developed sequencing approaches, we show that [m.sup.1]A is enriched around the start codon upstream of the first splice site: it preferentially decorates more structured regions around canonical and alternative translation initiation sites, is dynamic in response to physiological conditions, and correlates positively with protein production. These unique features are highly conserved in mouse and human cells, strongly indicating a functional role for [m.sup.1]A in promoting translation of methylated mRNA., Four decades after it was first observed as an abundant constituent of the eukaryotic transcriptome, [m.sup.6]A has only recently been revealed to broadly affect mRNA metabolism (1,2). Consequently, a broader [...]

The prevalent m6Am mRNA cap modification was recently identified as a valid target for removal by the human obesity gene FTO along with the previously established m6A mRNA modification. However, the deposition and dynamics of m6Am in regulating obesity are unknown. Here, we investigate the liver m6A/m methylomes in mice fed on a high fat Western-diet and in ob/ob mice. We find that FTO levels are elevated in fat mice, and that genes which lost m6Am marking under obesity are overly downregulated, including the two fatty-acid-binding proteins FABP2, and FABP5. Furthermore, the cellular perturbation of FTO correspondingly affect protein levels of its targets. Notably, generally m6Am- but not m6A-methylated genes, are found to be highly enriched in metabolic processes. Finally, we deplete all m6A background via Mettl3 knockout, and unequivocally uncover the association of m6Am methylation with increased mRNA stability, translation efficiency, and higher protein expression. Together, these results strongly implicate a dynamic role for m6Am in obesity-related translation regulation. m6A and m6Am are two prevalent mRNA modifications which are target for removal by the fat mass and obesity gene FTO. Here the authors capture the differential profile of these two modifications in the liver of obese mice and identify dynamic translation regulation by the m6Am modification. [ABSTRACT FROM AUTHOR]

While average human life expectancy has increased dramatically in the last century, the maximum life span has only modestly increased. These observations prompted the notion that human life span might have reached its maximal natural limit of ~115 years. To evaluate this hypothesis, we conducted a systematic analysis of all-cause human mortality throughout the 20th century. Our analyses revealed that, once cause of death is accounted for, there is a proportional increase in both median age of death and maximum life span. To examine whether pathway targeted aging interventions affected both median and maximum life span, we analyzed hundreds of interventions performed in multiple organisms (yeast, worms, flies, and rodents). Three criteria: median, maximum, and last survivor life spans were all significantly extended, and to a similar extent. Altogether, these findings suggest that targeting the biological/genetic causes of aging can allow breaking the currently observed ceiling of human maximal life span. [ABSTRACT FROM AUTHOR]

Polymorphism of the FTO gene encoding an N-methyladenosine (mA) RNA demethylase was robustly associated with human obesity; however, the mechanism by which FTO affects metabolism, considering its emerging role in RNA modification, is still poorly understood. A new study published in Cell Research reports novel functions implicating FTO in the regulation of mRNA alternative splicing in the control of adipogenesis. [ABSTRACT FROM AUTHOR]

The article focuses on the role of the N6methyladenosine (m6A) transferase Mettl3 in regulating the state transitions of naïve and primed pluripotency toward cell differentiation. It states a small interfering RNA screen was conducted against transcriptional regulators and tested if a primed EpiSC harboring a green fluorescent protein reporter knockin allele might rely on some of the factors. It comments that M6A messenger RNA methylation was a regulator acting at molecular switches.

Polymorphism of the FTO gene encoding an N(6)-methyladenosine (m(6)A) RNA demethylase was robustly associated with human obesity; however, the mechanism by which FTO affects metabolism, considering its emerging role in RNA modification, is still poorly understood. A new study published in Cell Research reports novel functions implicating FTO in the regulation of mRNA alternative splicing in the control of adipogenesis.