Cytochemical studies on golgi apparatus, GERL, and lysosomes in neurons of dorsal root ganglia in mice.

Abstract

Cytochemically demonstrable thiamine pyrophosphatase activity is present in the innermost Golgi element in both small and large neurons of the dorsal root ganglia in CF1, C57 black, and C57 beige mice, thus resembling the neurons of rat dorsal root ganglia. The localization of acid phosphatase (EC 3.1.3.2) activity in the large neurons of dorsal root ganglia in these mice is also similar to that in rats; it is not demonstrable in Golgi elements but is present in GERL and in three types of lysosomes apparently derived from GERL. However, the small neurons of the mouse differ from those of the rat in showing acid phosphatase activity in all elements of the Golgi apparatus. In the mouse* neurons the acid phosphatase activity of residual bodies is "latent," i.e., it is not demonstrable in well-preserved cells.The three organelles dealt with in this communication are closely related structurally, and probably functionally: (a) the Golgi apparatus, (b) GERL-a specialized region of smooth endoplasmic reticulum that is located at the "trans" (1) face of the stack of Golgi elements and that possesses cytochemically demonstrable acid hydrolase activities, and (c) lysosomes (2-4). In an early account (5), small neurons of dorsal root ganglia in 13-month CF1 mice were found to display acid phosphatase activity in the three organelles, including all "elements" (2) of the Golgi apparatus. "It remains to be established," we wrote, "if this difference from the rat findings reflects the difference in age ... or species" (5).Our present observations establish the difference to be a species difference between mouse and rat. Although acid phosphatase activity is demonstrable in the Golgi apparatus of the small neurons, the large neurons in the mouse dorsal root ganglia fail to show this activity. Another interesting difference between dorsal root neurons of mouse and rat is that in the mouse the type of lysosome known as residual body (3) does not reveal its acid phosphatase activity in well-preserved cells, i.e., this activity is "latent" as in lysosomes carefully isolated from liver homogenates (6). In contrast, two other types of lysosomes, coated vesicles and autophagic vacuoles of the type-2 variety (3), show acid phosphatase activity even when the residual bodies fail to do so. MATERIALS AND METHODSThree strains of mice were studied: CF2, purchased from Carworth Farms, Wilmington, Mass., homozygous C57 black/6J, and its beige mutant (bg/bg), both obtained from the Jackson t To whom reprint requests should.be addressed.Laboratories, Bar Harbor, Me. Animals of both sexes were used; they ranged in age from 8 to 26 weeks.As with rats, good preservation of neurons requires fixation by perfusion. Similar results were obtained by perfusion with 2.5% glutaraldehyde (Ladd Research Industries, Inc., Burlington, Vt.)-0.1 M cacodylate buffer, pH 7.4 with 0.05% CaCl2 (7) or with 2.5% glutaraldehyde-2% formaldehyde (prepared from paraformaldehyde purchased from Fisher Scientific Co.)-0.09 M cacodylate, pH 7.4, with 0.025% CaCl2 (8)...

The Three-Dimensional Structure of the Golgi Complex in Cultured Fibroblasts. An Ultracytochemical Study With Thin and Thick Sections

“…The Golgi complex shown in the present study is different from those reported in other tissues which are relatively isolated structures from each other (2,14,16,(20)(21)(22)(23)(24) : in human and mouse cultured fibroblasts the stacks of the cisternal part of the Golgi complex are relatively isolated from each other, while the continuous network of the reticular part exists as if it combines the isolated cisternal parts, thus integrating the whole Golgi complex as a single elaborate network system. Although Novikoff et al (2 1) once suggested that the GERL is a continuous structure throughout the cytoplasm, they did not show any persuasive pictures .…”

“…They considered the GERL the site of the formation of lysosomes of various types (2,16,19) and also of secretory granules of various kinds (20,22,23). In the present study on cultured fibroblasts, it was also suggested that the reticular part of the Golgi complex (GERL) is the site of the formation of primary lysosomes of two types, the coated vesicle type and the regular dense body type.…”

“…The Golgi complex and the "Golgi-associated smooth membrane system" (GERL) (16,21) have been intensively studied recently with ultracytochemical techniques (2,14,16,19,(20)(21)(22)(23). These studies indicated that the Golgi complex (or GERL) is not only the site of the formation of secretory granules but also the site of the formation of lysosomes of various types.…”

Association of a protease (plasminogen activator) with a specific membrane fraction isolated from transformed cells.

“…Thus, only 22% of the total TPPase activity is present in fraction B (Tables II and III). It should also be noted that TPPase has been shown to be a marker for Golgi membrane only in noncultured cells (7) and that its use as a Golgi marker in this study is based on inference. On the other hand, 5'-nucleotidase and Na +, K+-ATPase have been reported to be plasma membrane markers in cultured CEF (4,43).…”

“…Plasminogen was purified from fetal bovine serum or chicken serum by two passages over a lysine sepharose affinity column (47). The incubation mixture (1.0 ml) contained [5][6][7][8][9][10] /~g of purified plasminogen, 0.1 M Tris (pH 8.1), 0.02% Triton, and an aliquot of an RSV-CEF subcellular fraction (1-10 /zg protein). Aliquots were removed from duplicate petri dishes at 1, 2, and 3 h during incubation at 37~ and the radioactivity released was determined directly in an Intertechnique gamma counter (Intertechnique, Fairfield, N.J .).…”