Enhanced partner preference in a promiscuous species by manipulating the expression of a single gene

The molecular mechanisms underlying the evolution of complex behaviour are poorly understood. The mammalian genus Microtus provides an excellent model for investigating the evolution of social behaviour. Prairie voles (Microtus ochrogaster) exhibit a monogamous social structure in nature, whereas closely related meadow voles (Microtus pennsylvanicus) are solitary and polygamous. In male prairie voles, both vasopressin and dopamine act in the ventral forebrain to regulate selective affiliation between adult mates, known as pair bond formation, as assessed by partner preference in the laboratory. The vasopressin V1a receptor (V1aR) is expressed at higher levels in the ventral forebrain of monogamous than in promiscuous vole species, whereas dopamine receptor distribution is relatively conserved between species. Here we substantially increase partner preference formation in the socially promiscuous meadow vole by using viral vector V1aR gene transfer into the ventral forebrain. We show that a change in the expression of a single gene in the larger context of pre-existing genetic and neural circuits can profoundly alter social behaviour, providing a potential molecular mechanism for the rapid evolution of complex social behaviour.     

Genome-wide non-mendelian inheritance of extra-genomic information in Arabidopsis

A fundamental tenet of classical mendelian genetics is that allelic information is stably inherited from one generation to the next, resulting in predictable segregation patterns of differing alleles. Although several exceptions to this principle are known, all represent specialized cases that are mechanistically restricted to either a limited set of specific genes (for example mating type conversion in yeast) or specific types of alleles (for example alleles containing transposons or repeated sequences). Here we show that Arabidopsis plants homozygous for recessive mutant alleles of the organ fusion gene HOTHEAD (HTH) can inherit allele-specific DNA sequence information that was not present in the chromosomal genome of their parents but was present in previous generations. This previously undescribed process is shown to occur at all DNA sequence polymorphisms examined and therefore seems to be a general mechanism for extra-genomic inheritance of DNA sequence information. We postulate that these genetic restoration events are the result of a template-directed process that makes use of an ancestral RNA-sequence cache.     

Loss-of-function mutations in FGFR1 cause autosomal dominant Kallmann syndrome

We took advantage of overlapping interstitial deletions at chromosome 8p11-p12 in two individuals with contiguous gene syndromes and defined an interval of roughly 540 kb associated with a dominant form of Kallmann syndrome, KAL2. We establish here that loss-of-function mutations in FGFR1 underlie KAL2 whereas a gain-of-function mutation in FGFR1 has been shown to cause a form of craniosynostosis. Moreover, we suggest that the KAL1 gene product, the extracellular matrix protein anosmin-1, is involved in FGF signaling and propose that the gender difference in anosmin-1 dosage (because KAL1 partially escapes X inactivation) explains the higher prevalence of the disease in males.     

Lymphopenia and lymphocyte transformation in alcoholics

Summary The basis of peripheral blood lymphopenia observed in patients with chronic alcoholism and liver disease was investigated by examining the effect of sera of these patients on in vitro transformation of normal human peripheral blood lymphocytes. A positive correlation was demonstrated between the serum inhibition of phytohaemagglutinin- and pokeweed mitogen-induced transformation and the degree of lymphopenia. Thus serum factors may contribute to the observed lymphopenia by inhibiting lymphocyte production in vivo.This study was supported by grants from the National Health and Medical Research Council of Australia, Royal Australasian College of Physicians and Alfred Hospital Henry Laurie Scholarship Fund.     

猴鼻咽部的解剖学

本文对10个猴头的鼻咽部作了肉眼形态学观察,组织学观察及测量了鼻咽部的10个部位,并研究了猴鼻咽部的周界。我们观察到:1、猴鼻咽部有鼻咽中隔,它是鼻中隔向后的延续,因而不存在有鼻后孔,故不能以鼻后孔作为鼻咽前界的定位点。2、鼻咽中隔为猴所特有,不见于人和免,鼠等动物。鼻咽中隔把鼻咽腔分为左右两个相等的牛角管形的腔,耳咽管开口于鼻咽侧壁中部偏后的位置。鼻咽中隔内有丰富的淋巴组织,向后部淋巴组织逐渐减少并上移至鼻咽顶壁。3、鼻咽侧壁于耳咽管前后均可见肌组织,由前向后肌组织逐渐加多。4、本文对猴鼻咽部10个部位作了测量,其平均数为:鼻咽顶壁长27mm,鼻咽底壁长33mm,耳咽管口至鼻咽前界11mm,耳咽管口至鼻晒后壁7mm,外鼻孔至鼻咽前界55mm。本研究观察复盖猴鼻咽部各部位的上皮,均为假复层纤毛柱状上皮,未见有鳞状上皮。