diff --git a/apiserver/mongo/initialize/pre_populate.py b/apiserver/mongo/initialize/pre_populate.py
index c97202f..c711741 100644
--- a/apiserver/mongo/initialize/pre_populate.py
+++ b/apiserver/mongo/initialize/pre_populate.py
@@ -21,6 +21,7 @@ from typing import (
     Union,
     Mapping,
     IO,
+    Callable,
 )
 from urllib.parse import unquote, urlparse
 from zipfile import ZipFile, ZIP_BZIP2
@@ -54,6 +55,7 @@ from apiserver.database.model.task.task import (
 from apiserver.database.utils import get_options
 from apiserver.utilities import json
 from apiserver.utilities.dicts import nested_get, nested_set, nested_delete
+from apiserver.utilities.parameter_key_escaper import ParameterKeyEscaper
 
 
 class PrePopulate:
@@ -744,6 +746,19 @@ class PrePopulate:
         module = importlib.import_module(module_name)
         return getattr(module, class_name)
 
+    @staticmethod
+    def _upgrade_model_data(model_data: dict) -> dict:
+        metadata_key = "metadata"
+        metadata = model_data.get(metadata_key)
+        if isinstance(metadata, list):
+            metadata = {
+                ParameterKeyEscaper.escape(item["key"]): item
+                for item in metadata
+                if isinstance(item, dict) and "key" in item
+            }
+            model_data[metadata_key] = metadata
+        return model_data
+
     @staticmethod
     def _upgrade_task_data(task_data: dict) -> dict:
         """
@@ -828,9 +843,14 @@ class PrePopulate:
         print(f"Writing {cls_.__name__.lower()}s into database")
         tasks = []
         override_project_count = 0
+        data_upgrade_funcs: Mapping[Type, Callable] = {
+            cls.task_cls: cls._upgrade_task_data,
+            cls.model_cls: cls._upgrade_model_data,
+        }
         for item in cls.json_lines(f):
-            if cls_ == cls.task_cls:
-                item = json.dumps(cls._upgrade_task_data(task_data=json.loads(item)))
+            upgrade_func = data_upgrade_funcs.get(cls_)
+            if upgrade_func:
+                item = json.dumps(upgrade_func(json.loads(item)))
 
             doc = cls_.from_json(item, created=True)
             if hasattr(doc, "user"):