alpha-Fetoprotein (AFP) was shown to be the major secretory protein produced in vitro by normal rat yolk sacs. While not so active, AFP production was also detected in the transplantable tumors derived from normal yolk sacs. The major secretory protein synthesized by the tumor cells had a molecular weight of 40,000 and was reactive with an anti-rat albumin antibody. The functional messenger RNA...

PURPOSE Mucosa-associated lymphoid tissue (MALT) represents a part of the immune system located at mucosal surfaces. Its presence in the human eye is the point in question in the current study. Its occurrence, components, topography, and probable functional significance in the human conjunctiva and lacrimal drainage system were investigated. METHODS Fifty-three complete conjunctival sacs were...

Secretion occurs in all living cells and involves the delivery of intracellular products to the cell exterior. Secretory products are packaged and stored in membranous sacs or vesicles within the cell. When the cell needs to secrete these products, the secretory vesicles containing them dock and fuse at plasma membrane-associated supramolecular structures, called porosomes, to release their con...

The fine structure of the ergastoplasm of the pancreatic exocrine cell of Swiss albino mice has been studied with the electron microscope. It was found that this material consists of sac-like structures, which may be called ergastoplasmic sacs, embedded in an amorphous granular ground substance, the cytoplasmic matrix. The membranous wall of the ergastoplasmic sac is a structure approximately 2...

Results achieved in the molecular biology of Paramecium have shed new light on its elaborate membrane trafficking system. Paramecium disposes not only of the standard routes (endoplasmic reticulum --> Golgi --> lysosomes or secretory vesicles; endo- and phagosomes --> lysosomes/digesting vacuoles), but also of some unique features, e.g. and elaborate phagocytic route with the cytoproct and memb...

In ciliates, a variety of processes are regulated by Ca2+, e.g., exocytosis, endocytosis, ciliary beat, cell contraction, and nuclear migration. Differential microdomain regulation may occur by activation of specific channels in different cell regions (e.g., voltage-dependent Ca2+ channels in cilia), by local, nonpropagated activation of subplasmalemmal Ca stores (alveolar sacs), by different s...

In ciliates, a variety of processes are regulated by Ca', e.g., exocytosis, endocytosis, ciliary beat, cell contraction, and nuclear migration. Differential microdomain regulation may occur by activation of specific channels in different cell regions (e.g., voltagedependent Ca' channels in cilia), by local, nonpropagated activation of subplasmalemmal Ca stores (alveolar sacs), by different sens...

Secretory organelles are engaged in a continuous flux of membranes, which is believed to occur mostly via transport vesicles. Being critical in maintaining several cellular functions, transport vesicles are membrane-enclosed sacs that temporarily store and then deliver membrane lipids, protein, and polysaccharides. SNAREs have a crucial role in vesicle traffic by driving membrane fusion and con...

Because of sexual propagation of Mexican lime in southern regions of Iran, there are many lime accessions (lime biotypes) in Mexican lime gardens in which appear some variation in fruit and tree shape. However, most of these accessions are susceptible to witches broom disease of lime (WBDL). Persian lime (C. latifolia Tanaka) is a triploid WBDL-tolerant species. Considerable number of un-descri...