Hormones, genes, and behavior

With assays of hormone-sensitive behaviors, it is possible to demonstrate both direct and indirect actions of genes on mammalian social behaviors. Direct effects of estrogen receptor gene expression and progesterone receptor gene expression figure prominently in well analyzed neuroendocrine mechanisms for sex behavior, operating through a neural circuit that has been delineated. Indirect effects, notably the consequences of sexual differentiation, display complex dependencies. In a human condition, Kallmann syndrome, the data show a clear, indirect genetic influence on an important human social behavior, in which damage at chromosome Xp-22.3 works through at least six discrete steps to affect libido. Altogether, simplistic extrapolations from lower animals, especially during brief summaries for nonscientists, do not appear justified as we discover and conceptualize genetic influences on mammalian brain and behavior.

A total system approach to sustainable pest management

A fundamental shift to a total system approach for crop protection is urgently needed to resolve escalating economic and environmental consequences of combating agricultural pests. Pest management strategies have long been dominated by quests for “silver bullet” products to control pest outbreaks. However, managing undesired variables in ecosystems is similar to that for other systems, including the human body and social orders. Experience in these fields substantiates the fact that therapeutic interventions into any system are effective only for short term relief because these externalities are soon “neutralized” by countermoves within the system. Long term resolutions can be achieved only by restructuring and managing these systems in ways that maximize the array of “built-in” preventive strengths, with therapeutic tactics serving strictly as backups to these natural regulators. To date, we have failed to incorporate this basic principle into the mainstream of pest management science and continue to regress into a foot race with nature. In this report, we establish why a total system approach is essential as the guiding premise of pest management and provide arguments as to how earlier attempts for change and current mainstream initiatives generally fail to follow this principle. We then draw on emerging knowledge about multitrophic level interactions and other specific findings about management of ecosystems to propose a pivotal redirection of pest management strategies that would honor this principle and, thus, be sustainable. Finally, we discuss the potential immense benefits of such a central shift in pest management philosophy.

Polyadenylylated nuclear RNA encoded by Kaposi sarcoma-associated herpesvirus.

A newly recognized gamma herpesvirus known as Kaposi sarcoma-associated herpesvirus (KSHV) or human herpesvirus 8 (HHV8) is present in Kaposi sarcomas and body-cavity-based lymphomas. Here we identify a novel abundant 1.2-kb RNA, polyadenylated nuclear RNA (PAN RNA), encoded by the virus. The majority of cDNAs produced from poly(A)-selected RNA isolated from a human body cavity lymphoma cell line 48 hr after butyrate induction of KSHV lytic replication represented PAN RNA. Within PAN RNA were two 9 and 16 nt stretches with 89% and 94% identity to U1 RNA. A third stretch of 14 nt was 93% complementary to U1. The 5' upstream region of PAN RNA contained both proximal and distal sequence elements characteristic of regulatory regions of U snRNAs, whereas the 3' end was polyadenylylated. PAN RNA was transcribed by RNA polymerase II, lacked a trimethylguanosine cap, and did not associate with polyribosomes. PAN RNA formed a speckled pattern in the nucleus typical of U snRNAs and colocalized with Sm protein. Therefore, PAN represents a new type of RNA, possessing features of both U snRNA and mRNA.

Cellular expression of human centromere protein C demonstrates a cyclic behavior with highest abundance in the G1 phase.

Centromere proteins are localized within the centromere-kinetochore complex, which can be proven by means of immunofluorescence microscopy and immunoelectron microscopy. In consequence, their putative functions seem to be related exclusively to mitosis, namely to the interaction of the chromosomal kinetochores with spindle microtubules. However, electron microscopy using immune sera enriched with specific antibodies against human centromere protein C (CENP-C) showed that it occurs not only in mitosis but during the whole cell cycle. Therefore, we investigated the cell cycle-specific expression of CENP-C systematically on protein and mRNA levels applying HeLa cells synchronized in all cell cycle phases. Immunoblotting confirmed protein expression during the whole cell cycle and revealed an increase of CENP-C from the S phase through the G2 phase and mitosis to highest abundance in the G1 phase. Since this was rather surprising, we verified it by quantifying phase-specific mRNA levels of CENP-C, paralleled by the amplification of suitable internal standards, using the polymerase chain reaction. The results were in excellent agreement with abundant protein amounts and confirmed the cyclic behavior of CENP-C during the cell cycle. In consequence, we postulate that in addition to its role in mitosis, CENP-C has a further role in the G1 phase that may be related to cell cycle control.