The translational regulation of maternal mRNAs is the primary mechanism by which stage‐specific programs of protein synthesis are executed during early development. Translation of a variety of maternal mRNAs requires either the maintenance or cytoplasmic elongation of a 3′ poly(A) tail. Conversely, deadenylation results in translational inactivation. Although its precise function remains to be elucidated, the highly conserved poly(A) binding protein I (PABP) mediates poly(A)‐dependent events in translation initiation and mRNA stability. Xenopus oocytes contain less than one PABP per poly(A) binding site suggesting that the translation of maternal mRNAs could be either limited by or independent of PABP. In this report, we have analyzed the effects of overexpressing PABP on the regulation of mRNAs during Xenopus oocyte maturation. Increased levels of PABP prevent the maturation‐specific deadenylation and translational inactivation of maternal mRNAS that lack cytoplasmic polyadenylation elements. Overexpression of PABP does not interfere with maturation‐specific polyadenylation, but reduces the recruitment of some mRNAs onto polysomes. Deletion of the C‐terminal basic region and a single RNP motif from PABP significantly reduces both its binding to polyadenylated RNA in vivo and its ability to prevent deadenylation. In contrast to a yeast PABP‐dependent poly(A) nuclease, PABP inhibits Xenopus oocyte deadenylase in vitro. These results indicate that maturation‐specific deadenylation in Xenopus oocytes is facilitated by a low level of PABP consistent with a primary function for PABP to confer poly(A) stability.

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Since 2009, the U.S. National Science Foundation Directorate for Biological Sciences has funded Research Coordination Networks (RCN) aimed at collaborative efforts to improve participation, learning, and assessment in undergraduate biology education (UBE). RCN-UBE projects focus on coordination and communication among scientists and educators who are fostering improved and innovative approaches to biology education. When faculty members collaborate with the overarching goal of advancing undergraduate biology education, there is a need to optimize collaboration between participants in order to deeply integrate the knowledge across disciplinary boundaries. In this essay we propose a novel guiding framework for bringing colleagues together to advance knowledge and its integration across disciplines, the “Five ‘C’s’ of Collaboration: Commitment, Collegiality, Communication, Consensus, and Continuity.” This guiding framework for professional network practice is informed by both relevant literature and empirical evidence from community-building experience within the RCN-UBE Advancing Competencies in Experimentation–Biology (ACE-Bio) Network. The framework is presented with practical examples to illustrate how it might be used to enhance collaboration between new and existing participants in the ACE-Bio Network as well as within other interdisciplinary networks.

We present a complete staging table of normal development for the lungless salamander, Hemidactylium scutatum (Caudata: Plethodontidae). Terrestrial egg clutches from naturally ovipositing females were collected and maintained at 15 °C in the laboratory. Observations, photographs, and time-lapse movies of embryos were taken throughout the 45-day embryonic period. The complete normal table of development for H. scutatum is divided into 28 stages and extends previous analyses of H. scutatum embryonic development (Bishop, 1920; Humphrey, 1928). Early embryonic stage classifications through neurulation reflect criteria described for Xenopus laevis, Ambystoma maculatum and other salamanders. Later embryonic stage assignments are based on unique features of H. scutatum embryos. Additionally, we provide morphological analysis of gastrulation and neurulation, as well as details on external aspects of eye, gill, limb, pigmentation, and tail development to support future research related to phylogeny, comparative embryology, and molecular mechanisms of development.

Learner-centered teaching represents more than creating a course where students are actively engaged. Rather it is articulated by a shift in the balance of power, function of content, role of the instructor, purpose of assessment, and/or responsibility for learning in a course. To make the learning environment in a largeenrollment nonmajors Biology course more learner-centered, students were given the responsibility to: 1) select course topics, 2) determine the types and weights of course assignments used to assess learning, and 3) individually decide, prior to being assigned work, the weight of exams and projects. Combined survey results from two learner-centered sections of the course (n = 137) indicate that a majority of the students found that choosing the topics enhanced their learning of course material. Students also reported that they put more effort into the parts of the course that they had weighted more heavily. In addition, results support that students are reflective of the learner-centered environment, confident in their ability to learn biological topics and more interested in biology than they thought they would be. Finally, course averages from the learner-centered courses were significantly higher than course grades from instructor-centered versions of the course.