Mate-guarding success depends on male investment in a butterfly.

Males of many insects, including butterflies, produce mate-guarding devices, such as mating plugs, to prolong guarding and prevent future female matings in the male's absence. In a few butterflies, large external mate-guarding devices, that is, sphragides, occur. Gór et al.

Phenotypic senescence in a natural insect population.

Senescence seems to be universal in living organisms and plays a major role in life-history strategies. Phenotypic senescence, the decline of body condition and/or performance with age, is a largely understudied component of senescence in natural insect populations, although it would be important to understand how and why insects age under natural conditions. We aimed (i) to investigate how body mass and thorax width change with age in a natural population of the univoltine Clouded Apollo butterfly (, Lepidoptera: Papilionidae) and (ii) to assess the relationship of this change with sex and wing length.

Characterization of a novel oligodendrocyte cell surface molecule.

Cell-type-specific reagents have proven useful in the analysis of central nervous system (CNS) development and function. Most markers of oligodendrocytes are components of myelin sheath, which in the CNS is the specific product of oligodendrocytes. We have isolated a novel monoclonal antibody termed 2B10 which was raised against embryonic rat spinal cord tissue.

Calcium regulation of skeletal myogenesis. II. Extracellular and cell surface effects.

The process of myoblast fusion during skeletal myogenesis is calcium regulated. Suppression of fusion is obtained by lowering medium [Ca2+] and re-initiated by raising medium [Ca2+]. Previously, we showed that such changes in medium [Ca2+] produced concomitant changes in myoblast [Ca2+] and that a critical cellular concentration of calcium must be present in myoblasts for fusion to occur.

A cell surface antigen expressed by astrocytes and their precursors.

Increasing evidence suggests that astrocytes of the mammalian CNS are a heterogeneous population of cells that express a number of common characteristics. In most cases, astrocytes or their precursors contain a class of intermediate filaments, composed in large part of glial fibrillary acidic protein (GFAP). While the expression of GFAP immunoreactivity is a specific characteristic of astrocytes in the vertebrate CNS, not all astrocytes contain detectable levels of glial filaments, particularly during early development.