Establishment of homozygous knock-out sea urchins

Abstract

know of no comparative cross-cultural research on vocal rates of infant boys and girls nor on possible differences in caregiver speech to boys and girls across cultures. A non-signifi cant tendency for caregivers to speak more to boys was seen in our data (see Supplemental Results), and other possible cultural factors could also infl uence sex differences in infant vocal rates (see Supplemental Discussion).It is possible that the sex difference is not closely related to language capability -the CBR did not show a sex difference -but rather to a difference in the tendency to vocalize, perhaps owing to sex differences in motoric activity level in infancy [7]. Boys might be said to show higher quantity but not quality in protophone production. Another hypothesis can be formulated in conjunction with a proposed explanation for the high rate (thousands per day throughout the fi rst year) of human protophone production in both sexes (see Supplemental Discussion). The protophones appear to be produced largely endogenously -they are most commonly not directed toward other speakers, occurring at a rate of approximately four per minute even when infants are alone [8]. Even infants born more than two months prematurely and still in neonatal intensive care produce prodigious numbers of protophones [2]. Furthermore, as noted above, there is no sign that deafness reduces protophone rates [5].This audible endogenous motoric activity, usually produced by infants in comfort, might be motivated by its value as a fi tness signal for the altricial human infant, competing for parental investment [9]. One might then suggest that evolution has led to boys signaling their fi tness more frequently than girls because they are more vulnerable to death in the fi rst year [10]. This fi tness signaling hypothesis could be explored, for example, by correlating parental investment with infant protophone rates. We are, however, seeking other possible explanations for this unexpected sex difference in infant vocal rates (see Supplemental Discussion).

Regulation of dynamic pigment cell states at single-cell resolution

“…From an intense red sea star ( Fromia milleporella ) to a black and white striped brittle star ( Ophiactis savignyi ) to the variegated sea urchin ( Lytechinus variegatus), pigment is a pervasive feature of this phylum. Because of the molecular techniques now available for echinoderms, mechanisms controlling pigmentation in these animals are being revealed ( Hira et al, 2020 ; Liu et al, 2019 ; Wessel et al, 2020 ; Yaguchi et al, 2020 ). The purple sea urchin, Strongylocentrotus purpuratus , provides a molecularly tractable model organism to dissect the developmental importance of pigmented cells, and the biosynthesis of their pigment.…”

Temnopleurus reevesii as a new sea urchin model in genetics

“…(a) Mutation efficiency with Smad2/3 sgRNA and Cas9 mRNA injection. The length of PCR fragment for the wild type Smad2/3 is designed as 331 bp, and a mixture of 174 bp and 157 bp cleaved bands by CRISPR/Cas9 system were detected in mutant individuals (method for mutation analysis is in (Yaguchi et al., 2020)). The numbering ladder of the left side of the image shows the size marker of DNA fragment.…”

“…Next, we tried to edit a nonlethal gene: the pigment‐related gene polyketide synthase 1 ( Pks1 ) as previously published (Yaguchi et al., 2020). The knockdown and F0 knockout phenotypes for this gene have already been reported, and the results indicated that sea urchins can survive and remain healthy without Pks1 function (Liu et al., 2019; Oulhen & Wessel, 2016).…”

CRISPR/Cas9 mutagenesis reveals a role for ABCB1 in gut immune responses toVibrio diazotrophicusin sea urchin larvae

“…However, CRISPR/Cas9-mediated editing has highly variable efficiency in the F 0 generation, dependent on numerous factors including: the choice of physical delivery method, molecular delivery of CRISPR components, sgRNA length and sequence, cell type and organism (Zhang et al, 2016;Lino et al, 2018). In sea urchins, this technique has only been used in a handful of studies to date (Lin and Su, 2016;Shevidi et al, 2017;Liu et al, 2019;Wessel et al, 2020;Yaguchi et al, 2020), all of which have targeted genes in which a mutation confers an easily visualized, and previously established, phenotype.…”